M6 on Software

Translating Math Into Code

2012-01-03T09:06:00.000Z

"Discrete mathematical structures form the foundation of computer science."

This opening sentence resumes the article about: Translating math into code with examples in Java, Racket, Haskell and Python, that show how math is translated into code.

./M6

Value Proposition

2011-12-28T20:42:00.001Z

While reading about marketing and web site design if found this interesting small post about value propositionThis is business centric, since it states why should customers choose you instead of your competition, and every business people should have that clear on their head.

Here it is: Value Proposition: A free worksheet to help you win arguments in any meeting. Don't forget to check the related links. ./M6

.Net Reflector

2011-12-07T09:46:00.001Z

During a set of web systems migration, things went very wrong and a customer requested me help in setting the systems up again.
One of the systems was developed in the .Net platform, not one of my strongest technologies, and C#.
He was getting really desperate when I started helping, because there was already one technical person looking at it for almost two months...

We performed "pair debugging" in the production environment, since there was no development nor quality environment available.
One of the first things I've detected was that the application that did not work referenced another application, which was not available. Fortunately, that project was available as an assembly, so all that was required was to include the assembly in the configuration file and we were ready for the next challenge.

The next challenge was not easier to detect, since the errors reported mentioned a missing log directory. The problem, though, was not caused by the missing directory. Any error that occurred was logged, but since the log was not working, it reported a directory not found.
Scanning the configuration for the debug location, we tried "./debug", expecting that the debug directory to be relative to project. Unfortunately, that was not the case!
The debug was managed by the previously stated external project, so I needed to see the what the debug code was doing in order to understand how to solve the problem.
The solution came from .Net Reflector, a great tool that allows one to open a library and navigate through its source code.
After a while I was able to understand how the debug file was being written. The programmer that coded the open debug file function was lazy, in a pejorative sense, was did not account for a relative path, forcing one to configure the debug file location with a full path statement, which is not straightforward when one is using a common web hosting service...

Fortunately, soon after, I was able to discover the full path for the application, so we specified the debug path as "c:\..." and things start rolling.

If it wasn't for .Net Reflector, I would have taken a lot more time to find out why the "./debug" value was being ignored and the debug file was trying to be written in "c:\windows\...".
It's a great tool for all serious .Net developers, I truly recommend it.

./M6

Django Inline Forms

2011-10-28T12:34:00.000+01:00

Here's how to implement an inline display of a form in Django: Django Inline Forms../M6

HoloDesk - Direct 3D Interactions with a Situated See-Through Display

2011-10-28T12:01:00.001+01:00

A technology that allows Minority Report GUIs:./M6

PDF generation in Django

2011-10-12T18:32:00.000+01:00

Working with Django is very easy. And when it comes to output an PDF instead of an HTML page, simplicity still applies.Check this post: PDF generation with PISA in Django ./M6

Solr for Latin Languages

2011-10-06T19:18:00.000+01:00

Here's how to configure Solr for Latin Languages../M6

Eclipse Application Export Error

2011-09-23T09:33:00.001+01:00

Wierd Eclipse export error dependency satisfaction conflict generated by the “Generate metadata repository” option: Eclipse Application Export Error../M6

iOS Frameworks

2011-09-12T12:43:00.003+01:00

A curated catalog of iOS frameworks and classes for the pragmatic iOS developer: iOS Frameworks.

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Organizational Chart

2011-09-12T09:56:00.008+01:00

I've come across with this funny, sarcastic, yet, realistic, organizational chart from Manu:

What's your organization charted?

./M6

Painless Django Kickoff

2011-09-08T12:46:00.003+01:00

I'm learning Django and, so far, I'm enjoying it.
But putting it to work, as a simple development environment on my laptop, was harder than I expected. Specially when it came to install the MySQL-Python connector.

If you're starting with Django, or are having trouble setting Python with MySQL, maybe this will help: Painless Django with MySQL Install.

./M6

Three Things Clients and Customers Want

2011-08-30T11:08:00.003+01:00

Here's three things an entrepreneur should always have in mind while developing and selling:

1. Results. If you can offer a return on investment, an engineering solution, more sales, no tax audits, a cute haircut, the fastest rollercoaster, a pristine beach, reliable insurance payouts at the best price, peace of mind, productive consulting or any other measurable result, this is a great place to start.

2. Thrills. More difficult to quantify but often as important, partners and customers respond to heroism. We are amazed and drawn to over the top effort, incredible risk taking on our behalf, the blood, sweat and tears that (rarely) comes from a great partner. A smart person working harder on your behalf than you'd be willing to work--that's pretty compelling.

3. Ego. Is it nice to feel important? You bet. When you greet us at the door with a glass of white wine, put our name in the lobby of the hotel, actually treat us better than anyone else does (not just promise it, but do it)... This can get old really fast if you industrialize and systemize it, though.

The full original post, by Seth Godin: Three things clients and customers want.

./M6

How To Find Ideas For a Startup

2011-08-30T09:49:00.002+01:00

A small, but good, text describing How To Pick The Right Idea For Your Startup.

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Waterfall vs. Agile

2011-08-12T14:37:00.004+01:00

A simple description about both methods and when to choose one over the other: Waterfall v Agile: How Should I Approach My Software Development Project?

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Pentaho first impressions

2011-07-12T13:26:00.007+01:00

I've just went to a Pentaho presentation performed by Xpand IT.
It was the first opportunity I had to get some answers from someone close to the project and I must say, in general, it is what I was expecting.

The presentation was a bit technical, but I think it could not be otherwise since Pentaho is technical. What I mean is that it does not address one of the most important issues on an ETL project: funcional mapping.
Technically, it's all there, but I do feel the transformations could, and should, be easier to define and implement. Point and click is cool when one wishes to sell the product to management, but to do real work, it slows down the development process.
There are just too many clicks involved even for the simplest task, some could be avoided with a GUI revision focused on the user productivity. For instance, recording previous user tree filters, instead of writing the word every time one wishes to filter something, would save a lot of time to the end user.

Another weak point is the lack of rule mapping management and documentation. It does not have a clean nor fast way to see field mappings. If one wishes to see which fields are mapped or what transformation rules are implemented, one has to manually search all the transformations and click on its graphical representation in order to find them.
It's a lot of click when one has hundreds of tables, and thousands of transformation rules defined.
And, obviously, this lack of management reflects on the project documentation because one cannot generate access nor generate rule mapping reports.
This is a serious issue Pentaho should solve. Rule definition is the core of an ETL process and it is totally unacceptable that one cannot access it is a simple, fast and clear way.

On the strong side, Pentaho has a lot of connectors and operators already available. It's entirely written in Java, supports scripting languages and it's open source, through the Kettle project. All this means that it can be easily expanded, either through customization of its core or through the development of plugins.
It can work from the command line, which is excellent because it can be included a shell script, and it has it's own J2EE server, also excellent because it provides out of the box integration solutions. For instance, one can write a transformation that starts when a web service is called or a JMS receives a message.
It comes with some simple, fuzzy, functions that helps to clean data, but don't expect too much out of it.
It seems to scale well, mainly through parallelization, but orchestration can only be achieved manually.

In short, Pentaho can evolve a lot. Specially when it comes to the funcional part of the ETL. But even technically, it misses an orchestrator to help jobs orchestration.
Currently, as a data migration expert, I'm still not convinced that Pentaho can be used on "hard core ETL" projects where the functional mapping management, the development time and the data migration time window are critical points.

./M6

Drupal makes people life harder.

2011-07-11T17:08:00.008+01:00

Out of the box Drupal is not very good.
Actually, it is quite over simplistic...

When I see a piece of software, I instantly assume that it will be helpful to some people, but Drupal philosophy is quite the oposite, it deliberately makes people life harder.
When one installs a Drupal site, most people will not get a solution, they'll just get more problems to solve.
Drupal states to be, and I quote, "an open source content management", but after it has been installed, it's totally useless since no one can really manage any content except text. And let's be fair, in the 21st century, supporting only text is extremely limited.
So, in order to support other types of content, one has to install plugins, the same plugins that should already come in the Drupal core system.

Another mistake Drupal makes is it's lack of support for common SEO stuff. In such a competitive world, it's a total fail not to support meta tags out of the box, again, another plugin is required.

Only after a considerable set of plugins has been installed, activated and configured, Drupal starts to be useful.
I consider such philosophy a real mistake because Drupal misses the whole point of software making people life easier. With such a plug-in world, Drupal makes people life harder.
Sometimes it actually states "go and use Joomla!".

./M6

Speaking Avatars

2011-06-16T10:58:00.004+01:00

I've found SitePal, a speaking avatar solution.

The text-to-speech option itself is great for demos, videos and presentations.

./M6

No Capital? No Problem. What You Get For Free Is Priceless

2011-06-14T11:34:00.001+01:00

A small post about bootstrapping a business idea without money: No Capital? No Problem. What You Get For Free Is Priceless

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Drupal shows only front page

2011-06-10T11:34:00.007+01:00

Trocaqui has gone "mad".
It was working fine and, suddenly, it started to show the front page, no matter what link I selected nor what address I inserted in the address bar...
This was so critical that I could't even login into the system to put the system on maintenance mode while fixing the problem...

I've researched and it look to be an Apache mod_rewrite problem.
It started to look like a clean URL problem so I decided to try the non-clean URL format and voilá, Drupal started to responde correctly...
Using the /?q= format I was able to login, set the system in maintenance mode and disable the clean URL format.
By now, I was at least able to manage it.

When in a similar situation, just change the clean URL with the standard Drupal format, it's actually quite easy. Just insert a ?q= between the first / and the following character.
Here's an example: http://www.trocaqui.net/forum is equivalent to http://www.trocaqui.net/?q=forum.

While this was good enough as a starting point, it was not the best solution, thus I continued the quest for the real solution.

I cloned the production site on my testing environment and was able to reproduce the problem, which is a great first step.
While analyzing the problem, I've found out that my .htaccess was broke and tried to fixed it following the steps of others that had .htaccess and Clean URLs problems.
Once the clean URLs were disables, I was unable to set them on again since Drupal tests clean URLs and only allows them to be activated if they will work.

Here's what worked for me, I edited the .htaccess and fixed things by setting the following:

RewriteEngine ON
RewriteRule "(^|/)\." - [F]
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?q=$1 [L,QSA]

Have special attention to the RewriteEngine ON, it may be case sensitive.

I hope this is helpful for others with a similar problem.
./M6

10 Web Based Project Management Software

2011-05-10T17:38:00.001+01:00

Here's a useful set of project management software: 10 Web Based Project Management Software.

./M6

Codified startup advice

2011-05-02T11:29:00.001+01:00

Gabriel Weinberg has a great flowchart about startup advice: Codified startup advice

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Steve's story- Googler 13

2011-05-02T11:19:00.002+01:00

A small but inspiring story about Google employee number 13: Steve's story- Googler 13

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10 Books Every Entrepreneur Must Read From 2010

2011-04-13T19:29:00.000+01:00

Here's a list of books from 2010 that every entrepreneur must read: 10 Books Every Entrepreneur Must Read From 2010

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10 Rock Solid Website Layout Examples

2011-04-12T17:25:00.001+01:00

Here's some nice simple and clean web desing layouts: 10 Rock Solid Website Layout Examples.

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Starting Up: What I Wish Someone Had Told Me 4 Years Ago

2011-04-02T17:18:00.002+01:00

Great post about starting up.
Core message: focus and do it. Need some inspiration? Just think you're Milton from Office Space, tucked in the corner cubicle of Innotech, staring at the red stapler, and waiting for your next pay check.
What I Wish Someone Had Told Me 4 Years Ago

./M6

Google's driverless car

2011-04-01T04:56:00.000+01:00

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How to write a simple operating system

2011-03-02T09:52:00.001Z

I was reading Hacker Montly and found this interesting step-by-step article in issue 10 about How to write a simple operating system.

./M6

Startup Marketing by Hacker Monthly

2011-02-14T19:12:00.001Z

Hacker Monthly has a special, free, edition about Startup Marketing.
I trully recomend it for all entrepreneurs.

./M6

Automatic FTP

2011-02-10T14:18:00.002Z

I currently need to upload of some text files via FTP, but since some files are big, over 5Gb, I get a lot timeouts, which stops me from using the FTP mput command.
So, I've developed a small Python script to automate this task and avoid the timeouts.
It has the following features:

can be scheduled;
accepts file masks;
assumes a default local directory where the files to be uploaded are located;
supports text files only;
opens the connection for each file transfer in order to avoid timeout problems;

Here it is:


# -*- coding: iso-8859-15 -*-
'''
Automatic FTP
'''

import sys
import string
import ftplib
import os
import glob
import datetime

# Server name or IP address
__SERVER = "server.com"
# FTP username
__USER = "username"
# FTP password
__PASSWORD = "password"
# Default local directory were files are located to be uploaded
__DEFAULT_LOCATION = "C:\\ftp\\upload"

#
# Shows the time difference.
#
def showTimeDifference(init):
td = datetime.datetime.now()-init
print "in",td.seconds,"seconds (",td.seconds/60," minutes )."

#
# Transfers the files
#
def transferFile(ftpFile):
ftpInit = datetime.datetime.now()
file = os.path.basename(ftpFile)

print "\tTransfering:",file,

ftp = ftplib.FTP(__SERVER)
ftp.login(__USER, __PASSWORD)

ftp.storlines("STOR " + str(file).upper(), open(ftpFile))

ftp.close()

showTimeDifference(ftpInit)

print ""

#
# Get the files to transfer
#
def getTransferFiles(location, mask):
result = []
for file in glob.glob1(location, mask):
result.append(os.path.join(location, file))

return result

#
# Main
#
def main(args):
fileMask = ""
fileLocation = __DEFAULT_LOCATION
if len(args) == 2:
fileMask = sys.argv[1]
elif len(args) == 3:
fileMask = args[1]
fileLocation = args[2]
else:
print "autoFTP filemask [location]"
sys.exit(0)

print "Transfer files from",fileLocation,"to", __SERVER,"..."
ftpInit = datetime.datetime.now()
for file in getTransferFiles(fileLocation, fileMask):
transferFile(file)

print "Transfer competed",
showTimeDifference(ftpInit)

#
# Main
#
main(sys.argv)

After setting things up for one's needs, it's quite easy to use.
To transfer all .txt files starting with "A" from the default local directory, just:

python autoFTP A*.txt

To transfer all .xml files from a specific directory "Z:\test", just:

python autoFTP *.xml Z:\test

If one needs to adapt this to either get file, i.e. download, or to support binary file, just check the Python ftplib documentation, it's quite easy.

./M6

ZX Spectrum Relaunch!

2011-02-08T15:51:00.003Z

I belong to the ZX Spectrum generation.
I grew up with a rubber keyboard on the tip of my fingers and I've spent too much hours in a row in front of a black and white small television...

This revolutionary machine is almost 30 years old and to celebrate that there will be a brand new ZX Spectrum 48K, with the same old games and some innovations...

48K rocks! :)

./M6

The Math Behind Consulting Companies

2011-02-07T16:42:00.002Z

An entrepreur friend pointed me to this very interesting post about the math behind consulting companies.
Here it is: The unfortunate math behind consulting companies.

./M6

Fetching Lines From Big Files

2011-01-25T15:22:00.005Z

Today I had a DB2 bulk loading problem. I got a couple of rejected records on a 2G+ file. These kind of files are too big to be manipulated with conventional text editors, and even text editors that can handle such files are, usually, not very fast.
Since I was in Windows, I've open th MSYS shell, changed into the correct directory and typed

cat -n STPRRIMH.S.ULD.U110115.UN | grep 1943664 > MH.txt

This is an instantiation of a more generic command

cat -n < file > | grep < line >

In a few seconds I had a new file containing exactly the information I needed.

Serious developers can't really live without Unix/Linux tools on their machines...

./M6

Haiku - BeOS Lives

2011-01-05T14:44:00.002Z

It seems BeOS is still alive and truying to kick.
A new open source project named Haiku is BeOS compatible multimedia oriented as the original project.

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Google Goggles Visual Search

2011-01-04T17:14:00.001Z

Visual search from Google Andoid:

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Never Steal a Hacker Machine

2010-12-30T11:30:00.001Z

Here's what happens when you steal a hackers computer:

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Geek and Gamer Girls Song

2010-12-30T09:18:00.001Z

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GWT Tutorial

2010-12-28T14:51:00.003Z

I'm starting to develop a SaaS application and I'm evaluating GWT.
Here's a simple tutorial for starters: GWT Tutorial – Introduction to GWT

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The Business of Software

2010-12-27T11:38:00.001Z

Here's a great post from Seth Godin about The Business of Software.

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Why PHP Is Fun and Easy But Python Is Marriage Material

2010-11-05T15:47:00.003Z

Dharmesh Shah has a great article about hard decisions, startups and technology.
A must read for all tech startups: Why PHP Is Fun and Easy But Python Is Marriage Material

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Life = Risk, Embrace it Naturally

2010-11-04T16:01:00.002Z

A great motivational video for all that believe in themselves

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Chris Anderson: How web video powers global innovation

2010-09-21T11:46:00.001+01:00

Has Seth's Godin states:
"Online video radically changes the reach and speed of the improvement cycle. Things like dance, snowboarding and TED talks keep getting better, and faster, because artists see the best and improve on it. Even more than that, it requires you to top what's out there, or you'll be ignored."

./M6

Hug a Developer

2010-09-21T11:38:00.001+01:00

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Interpreting DB2 JDBC error messages

2010-09-08T11:18:00.009+01:00

Every time I use DB2 on a data migration project I get awkward DB2/JDBC errors, no matter if I'm using DB2 on Windows, Unix or iSeries AS/400.
Part of the problem is that the error messages come in Portuguese, making the debug task a lot harder since it's almost impossible to find decent help by searching through the error messages. The other part of the problem is that this leaves me the SQL error codes, which sometimes are unclear and makes me waste time.
Here's an example of a common problem that I usually have:

com.ibm.db2.jcc.b.rg: [jcc][t4][102][10040][3.50.152] Non-atomic batch failure. The batch was submitted, but at least one exception occurred 
on an individual member of the batch. 
Use getNextException() to retrieve the exceptions for specific batched elements.

com.ibm.db2.jcc.b.pm: Error for batch element #1: The current 
transaction was rolled back because of error "-289".. SQLCODE=-1476, 
SQLSTATE=40506, DRIVER=3.50.152

com.ibm.db2.jcc.b.SqlException: [jcc][103][10843][3.50.152]
[...] ERRORCODE=-4225, SQLSTATE=null

Following DB2 official documentation:

SQLCODE=-1476 means that the current transaction was rolled back because of error.
SQLSTATE=40506 means that the current transaction was rolled back because of an SQL error, which is basically the same as the SQLCODE above.
ERRORCODE=-4225 means an error occurred when data was sent to a server or received from a server, which is totally useless.

The real useful information is hidden in the second error message, in the 'transaction was rolled back because of error "-289"' message. The key here is the -289 error.
This error means "Unable to allocate new pages in table space", and this is the real cause for such a big fuss.

One of my DB2 table spaces run out of space and all I get is a lot of fuss about a rollback that happened because of an error but the error itself is kind of hidden in the middle of the stack trace, all that is shown is a loose error code...
IBM has done it again, the cause of the error should be highlighted and perfectly visible and understood in order to know what really happened and fix the problem, but making the life easier for its users seems not to be IBM way.

./M6

Isaac Asimov on Bill Moyers World of Ideas

2010-08-31T09:15:00.003+01:00

1988 Interview with Isaac Asimov by Bill Moyers about learning, computers, religion, population growth, the universe.

It's fantastic how Asimov previewed the usage and impact of internet in 1988

Part One

Part Two

./M6

Writing your own traceroute in Python through 8 easy steps

2010-07-29T17:20:00.001+01:00

Great post in Kslice on implementing traceroute in Python:
Learning by doing: Writing your own traceroute in 8 easy steps.

./M6

MySQL Partitioning

2010-06-24T14:02:00.003+01:00

I was researching about MySQL performance for a new web project when I came across whit partitioning.

After reading Improving Database Performance with Partitioning and MySQL Partitioning, I thought "this is great, I'll use it", but after reading MySQL partitions tutorial, and since I'm using InnoDB, I though "maybe this is not such a good idea since storage may be a problem and the performance boost may not be that significant for this project".

In short, one has to perform some tests in order to decide.
./M6

List of Free and Open Source Software Packages

2010-05-26T23:07:00.004+01:00

I was searching for a Linux application server when I came across with this useful
list of free and open source software packages.

It's a great starting point when one knows what one needs but doesn't really have a reference.

./M6

ATI Mobility Radeon X700 on openSUSE

2010-05-21T22:29:00.002+01:00

As I've previously posted, I'm now using openSUSE and my ATI Mobility Radeon X700 was not fully functional.

After some investigation, I've found out that AMD no longer supports old ATI video cards for Linux.
I've even tried http://wiki.opensuse.org/SDB:ATI_drivers but with no luck.

Definitely this is one extra point for nVidia. When I replace my current laptop, it will have an nVidia card, that's for sure.

./M6

Drupal vs Joomla!

2010-05-06T15:35:00.001+01:00

I've launched a new free item exchange service for the Portuguese speaking community: Trocaqui.
I've implemented it using Drupal, for the user front-end, and that raised a lot of questions. Many people asked me, "why Drupal and not Joomla!" and "you're using a CMS, what's the difference between Drupal and the others".
So, I've decided to write a bit about the Trocaqui project and why Drupal.

When I started the project, I've (obviously) evaluated some options, writing from scratch, using a framework, using a CMS, etc.. I did not wish to code it from scratch nor to use some framework that would left all the hard work to me. I already knew Mambo, Joomla! and Drupal. From those I've used Mambo, which I've dropped in favor of Joomla!, since it is like the natural evolution of Mambo.

After some analysis, I've came to the point where it was either Joomla! or Drupal. I grabbed them both and perform some tests to see which would respond best to my main requirements:

Translatable (i18n for Portuguese)
Easy to use for the end user
Extensible
Expandable
Forum support
Image management support
Flexible and easy user access configuration setup
Easily costumizable

I've begun the tests by setting up the systems which was an easy task for both of them.

Joomla! is ready to be used just out-of-the-box. It allows one to manage text and images, it comes with a WYSIWYG text editor and is quite easy to understand. Almost everything is where one expects it to be. So, finding an option and using it is straightforward.
On the other hand, Drupal is not so usable out-of-the-box. It just supports text and doesn't came with an WYSIWYG editor.

So, some additional modules were necessary in order to expand Drupal to support my needs.

When it comes to module/plugin installation, in Drupal it is totally manual, so are the upgrades.
One has to uncompressed the file contents into a specific directory, the go to the modules section in the administration menu to activate it. Then one has to configure it.
Sometimes this is not as easy as it seems and some technical background is required in order to setup things correctly.

Drupal does not come with a WYSIWYG text editor.
Since I needed a rich text editor, I had to test editors before selecting one that worked as I needed. It was a bit painful because I had to test some and that took more time than I was initially expecting.

Drupal does not come with an image module.
A content management that cannot manage much beside text is not very useful.
Thus, the quest of an image module began. I've found Drupal has many modules that support images. And I've also found out that the reason for this proliferation of image modules is that because they all suck. There's not one good image module for Drupal, so it seems that everyone that needs one, develops one.
After some digging and testing, I've finally found an image module that suited half my needs. After some more digging, I've found another module that was suited for the other half of my needs.
Everyone that needs images on their CMS should check if Drupal modules fit their needs before going for Drupal.

Drupal working philosophy is not straightforward.
In Drupal, things are not were one expects it to be. It works with a organization and, to me, it complicates things, making it far more complicated that it should and needed to be.
Even today sometimes I take 10 or 15 seconds looking around for a specific option. It is not administrator friendly, specially if you don't work with it often.

None came with a forum solution, so I had to install one on each of the systems.

Finally I've finished setting up the systems.
Drupal had been painful so far, and I was loosing some consideration about it. But people do refer to it as a great CMS, so I decide to continue according to my plan.

It was time to evaluate things regarding my functional needs.
An here's the turning point favoring Drupal.

Joomla! does not come with flexible user parameters. But Drupal does.
In Drupal, the core user module allows one to defined specific parameters and corresponding value types in a very easy way. Probably Joomla! allows it to, but I didn't invest much time searching for such a module/plugin.

Joomla! does not allow drag-and-drop.
In Drupal, it is easy to move things using the mouse, just drag that menu option and drop it where you want it, do this option as many times as needed and the push the save button. This seems a minor issue, even from me (I'm a less WIMP than the average), but the amount of work that I was performing with such easiness allowed me to be far more productive than doing the same similar task in Joomla!.

Everything was going fine until I found a show stopper bug. I had so many exchange categories that Drupal stop ignoring the exchange category order I was specifying.
Not even the weights were working. I even tried banging directly on the database, but even though the items were not showing up in the correct order.
This forced me to stop the project for some weeks while finding the solution.
I did found out that I was not the only one complaining about this bug, it is know for years but yet, Drupal seems to be ignoring it.
I had posted this problem in Drupal forum but was starting to think in abandon Drupal because it seemed that there was no solution .
But suddenly a specific module for my problem came from Ben. He was just fantastic in helping me with this problem, he developed a small module, with a few lines of code, that solved the problem. I was on the move again.

I needed to create a template for the user to use when posting a new exchange item.
This revealed the true power of Drupal and why technical people love it. In Joomla! I needed to bang the forum module source code and use that modified module and, when a new version came out, do the same.
In Drupal I only needed to create a hook. A hook is like a handler that overrides the original code. You just say, when this event happens, I wish to do such and such. It was not easy to find out the correct data in the data structure that I needed to modify, I was new to Drupal programming. But once I've found the data I needed to modify, it revealed simple, easy and clean. I was dazzled with such simplicity and by then I had no doubts whatsoever that Drupal was the way to go.

Translating things to Portuguese also revealed much easier in Drupal. Both systems do have translation files for their modules, but Drupal allows one to translate things on the fly. Drupal has a translation interface that does not require the user to edit the translation file and upload it into the server.

Permission configuration also revealed a bit simpler in Drupal. I've just configured the read, write and administer accesses of each module for registered and non-registered users.

Finally I wanted to create a specific home page to show to everyone that landed on the site.
I've never done such thing in Joomla! and frankly, by then, I did not bothered to see what solutions were out there for this.
In Drupal there's a specific front page module that is just fantastic. I've created a specific home page for non authenticated users and another to authenticated users. It was just simple.

After all this quest here's what I've learned:
I recommend Joomla! for non-technical people and for web sites that do not require awkward requirements. It's great out-of-the-box and much easier to work with. But when things get though, you'll need a technical guy and you'll want Drupal supporting your site, even if it costs you a lot of time to learn how to use it.

./M6

Common MySQL Queries

2010-04-19T14:59:00.002+01:00

While looking for a MySQL Rank function, which does not currently exist, I've found this useful Common MySQL Queries.

./M6

Drupal contact limitation

2010-04-06T13:55:00.003+01:00

I've just set up a Portuguese speaking item exchange free service, named Trocaqui, based on Drupal. And I'm, obliviously, the website administrator.

I was contacting some of the earliest registered users when Drupal showed the following message:

Não pode contactar mais do que 3 utilizadores por hora. Por favor, tente novamente mais tarde.

It means "You cannot contact more than 3 users per hour. Please try again later.".
What kind of stupid limitation is this? I do understand this limitation when applied to common users, but the administrator?
Seriously, why can't the administrator use his own system without artificial limitations?

I've searched the subject and found out that, obviously, I was not the only one complaining about this for years, and there is no real workaround for it. So, I've just increased the number of messages per hour and will have to reconfigure it back when I finish the user contact task.

./M6

Database Models Library

2010-03-19T13:31:00.003Z

I've just found this library of database models. It is a big collection of database models useful for faster kick-offs.
It is hosted by Database Answers and there are far more useful information there. It's a great resource.

./M6

SWT File Dialog

2010-03-15T17:23:00.006Z

During the development of an Rich Client Platform (RCP) I needed to perform a file browse, here's how to show a file dialog in SWT:


import org.eclipse.swt.widgets.FileDialog;

FileDialog dialog = new FileDialog(this.getShell(), SWT.NULL);
dialog.setFilterExtensions(new String[] { "*.txt", "*.*" });
dialog.setFilterNames(new String[] { "Text files", "All files" });
String path = dialog.open();
if (path != null) {
 File file = new File(path);
 if (file.isFile()) {
  System.out.println(file.toString());
 }
}

The snippet above filters by text files (*.txt) and all files (*.*) only, and it can be easily applied to any button or file menu option click event.

./M6

Java Virtual Machine Process Status Tool

2010-02-24T15:15:00.003Z

Do your know jps?
It's the Java Virtual Machine Process Status Tool, which means it will show the status of your java processes.
Ever had the need to kill a Java process from an endless list of Java processes running on a server?
Just type jps -m to discover the PID of the process you wish to kill...

./M6

Panjiva

2010-02-22T14:08:00.002Z

Panjiva is an interesting search engine dedicated to company business.
It has interesting business and marketing features for markets and companies.
The search/index algorithm seems to need some tuning, some searches result non-relevant results in top places.

./M6

SaaS Metrics – A Guide to Measuring and Improving What Matters

2010-02-19T17:01:00.002Z

I've came across with this great post about Software as a Service metrics aimed to improve what matters, essentially cash, profitability and growth.

Here it is: SaaS Metrics – A Guide to Measuring and Improving What Matters

./M6

Sunny Bates on Passion, Fear and Balance

2010-02-15T10:14:00.002Z

I'm not afraid to fail. It's not trying that scares me...

Via Seth Godin on Vimeo.

./M6

Execute Commands Inside DB2 Procedures

2010-02-09T10:57:00.002Z

I was looking for a way to call DB2 runstats, a non-SQL command, from inside a store procedure.
It turns out that it is actually quite easy. All one has to do is to use the ADMIN_CMD procedure from the SYSPROC schema.

ADMIN_CMD is used by applications to run DB2 command line processor administrative commands using the SQL CALL statement.

Here's how to do it: ADMIN_CMD

./M6

How Technology Can Screw Business

2010-02-03T11:08:00.005Z

I'm searching for an automatic SMS send service, something sending a SMS via a web service.
Somehow two of the biggest Portuguese mobile operators, TMN and Optimus, don't provide this information on their web site, contrary to Vodafone that explains all their solutions and provides the corresponding prices and conditions.

This has forced me to contact the operators personally, so that their sales team can engage in a conversation with me and try their sales techniques that I'm already immune to.
For TMN I've requested that they call me back "immediately" as their form option said, but no phone call came from them. Maybe its because I'm competitor customer and they don't wish to make business with me. Or maybe it's just the form submission that didn't work. Whatever has happened, TMN did not called me back.
For Optimus, I've sent them an email to a specific email address that they provide in their web site. Here's the response:


Delivery has failed to these recipients or distribution lists:

16939@optimusnegocios.pt
The recipient's mailbox is full and can't accept messages now.
Microsoft Exchange will not try to redeliver this message for you.
Please try resending this message later, or contact the recipient direct

Isn't it great when technology screws your business big time?

I don't know what happened with TMN, but clearly something went totally wrong. It may have not been a technical problem, but in that case my contacts were loaded in their call center database and they've should have called me by now.

When it comes to Optimus, well, the answer is clear. Someone forgot to delete some old mails, haven't they? Or someone goofed big time with Microsoft Exchange Server, why is it configured to ignore customers? (Side Note: I love the last sentence where I should "contact the recipient direct", what am I doing by sending the recipient a direct email? I'm not contacting it through a middle man...)

Whatever the problem was, I'm almost positive that it was technical and that is how technology can screw business: by pushing them to competitors. What would their shareholders react if they knew this?
Good work Vodafone, it seems you're the one and only Portuguese mobile company that truly cares about your customers, at least you don't ignore them.

./M6

Data Visualization

2010-01-12T13:25:00.002Z

Data visualization changes the way people capture, understand, and even recall information.

Here's a five minutes presentation on the subject:

./M6

Open XML: The Markup Explained

2010-01-05T17:09:00.003Z

I've just found an ebook that technically explains the Open XML format in a simple way with some examples. It's great for all that wish to start using this format.

Here it is: Open XML - The markup explained.

And for more information, check out the OpenXML Developer.

./M6

ZON ISP (Bad) as Usual

2009-12-22T11:19:00.008Z

I'm considering changing my Internet Service Provider (ISP).

I currently have a optical fiber connection, fiber to the home (FTTH), from TVTel at 30Mbit/s.
But TVTel was acquired by ZON and so I'm considered migrating to it, since the value for money seems better, at approximately the same cost I can get a 50Mbit/s optical fiber connection.

But ZON has three major problems:

Extremely bad reputation when it comes to ISP;
Lousy customer service;
the ZON optical fiber solution is not FTTH.

They are fighting the first couple of problems and the fact is that the number of complaints against them has seen a serious decrease.
But all this made me delay the decision for some months, to see if there were other ISPs that would provide me FTTH.
Unfortunately no one else provides FTTH on the area, and since ZON seems to be discontinuing the TVTel infrastructure that they bought, that leaves the optical fiber to the local node and coaxial cable solution.

So, I decided to give it a try, specially because there is a one month trial period were one can cancel the service if one is not satisfied.
And currently, I'm not a satisfied customer. The 50Mbit/s connection on the signed contract is actually working at less than 10% of the speed.
Here is this morning speed measure from the organization responsible for the internet in Portugal, Fundação para a Computação Científica Nacional
(FCCN), where it says that this morning I almost got an "astonishing" 5Mbit/s connection:

ZON internet connection speed meter.

Look at the red graph speed on the right of the picture. Yes, it says that if we were in 2002 and using an ADSL 4Mbit/s connect that would be great. Unfortunately this we're on the end of the first decade of the 21st Century and I have a signed contract for 50Mbit/s.
For details, check the numbers on the left, the first number is the maximum download speed, the second is the average download speed, the third is the maximum upload speed and the fourth is the average upload speed.
There's no doubt what so ever, ZON optical fiber connection is easily beaten by a 8Mbit/s ADSL connection.

Here's the download information detail

ZON internet download speed.

Check the graphs on the bottom. It not even gets close to 5Mbit/s and the average speed is just above 1.2Mbit/s and the speed is just not constant, it jumps up and down.
Remember that this is an optical fiber 50Mbits/s connection.

And here is my current TV Tel 30Mbit/s download speed data, taken immediately after I got the lousy speed from ZON.

TVTel internet download speed.

The average speed is just below 22MBit/s, the first value on the left. The maximum speed is just above 22MBit/s and the minimum speed is just above 20Mbit/s. The connection is stable, regular, linear, smooth and, above all, fast!

Let me correct my first sentence on this post: "I was considering changing my ISP", because with a service like this one, ZON will definitely not get a contract with me.
But the first ISP that provides me FTTH will probably.

./M6

Recovering from a bad Hard Disk Crash

2009-12-16T16:52:00.004Z

Last time I've used my computer I burned a DVD Video with K3B and shutdown openSUSE as usual.

Yesterday, when I turned the computer on, it went directly into GRUB shell which allowed me to execute some commands with no real use to me.

Obviously something was wrong, and I though that it was the Master Boot Record (MBR) that got corrupted, as I've already have experienced before.
So I got the openSUSE installation disk and boot with it in order to fix the problem. I've requested the fix option from the menu but then something weird happened.
When scanning the hard disk, it displayed a message that there was something wrong and I would not be able to edit the disk partitions. I checked the partitions and the information seems to show that everything was OK.
I needed something else to see what was wrong with the hard disk and to fix it.

I grabbed an old Knoppix CD, version 3.3, the only one that I know that loads correctly on my Acer laptop (by the way, don't by an Accer if you wish to have Linux on a laptop), and checked the disks. This is not the first time I use Knoppix to save a system, it's actually one of my companion disks.
Knoppix automatically mounted both windows partitions correctly but the Linux EXT4 and Swap partitions were missing.
Now I start to get worried...

I got into a shell and checked the partitions with fdisk.
I detected the problem immediately: I had two partitions starting at the same cylinder! I even recall its number, 2086.
The second partition had an Id of f, which is awkward since the Id is a numeric value, and was marked as the boot partition. Using fdisk to see what my chances were of correcting this I realized that a drastic solution would probably be the only solution. When I deleted that second weird partition, the following partitions were gone to.

So, before I do something that I could regret latter, I checked the content of the Windows partitions to find out that if anything would go wrong I already had a backup of everything.
The data on the Linux partition seemed already lost, so I would have to settle for the backups.
On the other hand, I was still able to save everything from the Windows partitions, but that would be unecessary.

I finally decided what to do and how to do it.
I've deleted that second weird partition, defined the first partition as boot and saved the partition table.
I could have tried to recreate the partition table with fdisk, but since I had backups of everything, I just went for the full disaster scenario.

I then rebooted with the openSUSE installation disk, created a second partition, that I reserved to replace the lost second partition for Windows, and created a third one for Linux, where I installed openSUSE.

When openSUSE installation finished I've reboot and started Windows, which loaded just fine from the saved first partition. When Windows loaded, it was time to format that previous reserved second partition as NTFS.

The whole thing took me a couple of hours but I got both Windows and openSUSE up and running again. Today I'll restore the backups, which will probably take a couple hours more.

Moral of the story:

Always have a Knoppix disk at hand.
Backups are a tech best friend.

./M6

Distribute Python Applications on Windows

2009-12-11T13:30:00.003Z

How to distribute Python applications on Windows with py2exe and InnoSetup.

./M6

Source Code Format in Blogger

2009-12-10T16:18:00.002Z

Here's a simple tutorial to post formatted source code on Blogger:
Getting code formatting with syntax highlighting to work on blogger.

./M6

openSUSE

2009-12-08T22:26:00.006Z

I've just moved from Kubuntu to openSUSE.
The reason is simple, Kububtu 9.10 revealed too unstable for me. In just a couple of months I had to reinstall once and when troubles reappear for the second time, I talked with a friend and decided to give a try to openSUSE.

So far, so good. It's a lot more stable and my hardware seems to be better supported, even my ATI Mobility Radeon X700 that always gave me headaches in Linux works fine. Unfortunately the 3D support seems not be be fully working, but that is not a issue, at least for now.

I kept KDE as my window manager, it suits better my needs. The first look and feel at it was very pleasant. Even the desktop wallpaper is very good.
One of the first things I've learn was to add the Packman repository, since the default official repositories does not have some software for "some legal uncertainties". For instance, it does not have the mpeg2enc from mjpegtools, one has to remove the mjpegtools, add the Packman repository and add the mjpegtools again in order to have the Packman mjpegtools package installed, which does have the mpeg2enc.
Other great software, like 'Q' DVD-Author and DeVeDe, also comes from the Packman repository, so it is critical to include it.

Some things are different, specially when it comes to the administration part. Maybe it is because openSUSE has so much affinity with SUSE servers, it has a lot of easy administration tools right out-of-the-box.
But some things seem the same. The Network Manager still sucks. Why is it so hard to use, specially when its flag is "Pain-Free Networking"? Since Network Manager appeared, all it gave me was problems. In Kubuntu it simply did not connect via wifi, and now I can't enable it, even after I defined it to be my network manager and enabled it!...

Anyway, everything seems to work just fine and I'll keep openSUSE for a while, specially because it seems very stable.

./M6

DB2 How To

2009-12-07T14:07:00.002Z

While I was searching for the loading method that accepted a dynamic query from inside a stored procedure, I found a simple and very useful DB2 How To.

Here it is: DB2 How Tos.

./M6

DB2 Copy Schema With Tables

2009-12-03T16:24:00.004Z

Recently I needed to automate a DB2 schema backup.
My requirements were quite easy, just create a new schema and copy the tables and their content into the new schema.

What initially started as a simple task reveled to be a hard task and resulted in a quite simple script.

The first problem was to execute several commands in the DB2 Command Editor. I was getting syntax errors because the statement termination character was set to be the same as the SQL end statement character ;.
Setting it to # solved my problem, but I did waste some time with this so keep in mind to change the statement termination character to avoid such problem.

I've created a specific schema for this automation task COPY_DATABASE_SCHEMA, so all the procedures will be created there.

Here is the procedure that will copy a table content:


/**
* Copies, with replacement, the content from the source table
* into the target table.
* It will not check for success, i.e. no loading validation
* will be performed.
*
* @sourceTable: the full qualified source table name
* @targetTable: the full qualified target table name
*/
create procedure COPY_DATABASE_SCHEMA.COPY_TABLE(
sourceTable VARCHAR(128),
targetTable VARCHAR(128))
LANGUAGE SQL
begin
declare v_version_number INTEGER default 1;
declare v_cursor_statement VARCHAR(32672);
declare v_load_command VARCHAR(32672);
declare v_sqlcode INTEGER default -1;
declare v_sqlmessage VARCHAR(2048) default '';
declare v_rows_read BIGINT default -1 ;
declare v_rows_skipped BIGINT default -1;
declare v_rows_loaded BIGINT default -1;
declare v_rows_rejected BIGINT default -1;
declare v_rows_deleted BIGINT default -1;
declare v_rows_committed BIGINT default -1;
declare v_rows_part_read BIGINT default -1;
declare v_rows_part_rejected BIGINT default -1;
declare v_rows_part_partitioned BIGINT default -1;
declare v_mpp_load_summary VARCHAR(32672) default NULL;

set v_cursor_statement =
    'DECLARE C1 CURSOR FOR SELECT * from ' || sourceTable;
set v_load_command =
    'load from C1 of cursor insert into ' || targetTable;

call db2load(1, v_cursor_statement, v_load_command, v_sqlcode,
          v_sqlmessage, v_rows_read, v_rows_skipped,
          v_rows_loaded, v_rows_rejected, v_rows_deleted,
          v_rows_committed, v_rows_part_read,
          v_rows_part_rejected, v_rows_part_partitioned,
          v_mpp_load_summary) ;
end#

Please note that the target table must already be created in order for this procedure to work.
This procedure was the hard part. Copying the contents of any table requires a dynamic prepared query statement to use as a cursor, and the load command is not available inside a procedure, so the db2load procedure from SYSPROC must be used.

Here is the procedure that will create a schema, create the tables on it and copy the contents:


/**
* Copies an entire schema into a new schema named with the current date.
* @sourceSchema: the source schema name
* @targetSchema: the target schema name
* @tableNameSelection: the tables name to include ('%' for all tables)
*/
CREATE PROCEDURE COPY_DATABASE_SCHEMA.COPY_DATABASE(
sourceSchema VARCHAR(50),
targetSchema VARCHAR(50),
tableNameSelection VARCHAR(150)
)
LANGUAGE SQL
BEGIN
-- Variables
DECLARE stmtSchema VARCHAR(250);
DECLARE stmtTableStructure VARCHAR(200);
DECLARE stmtTableContents VARCHAR(250);
DECLARE stmtAlias VARCHAR(250);
DECLARE tableName VARCHAR(128);
DECLARE numPages BIGINT;
DECLARE nError INTEGER DEFAULT 0;
DECLARE at_end SMALLINT DEFAULT 0;
DECLARE not_found CONDITION FOR SQLSTATE '02000';
DECLARE V_SQL VARCHAR(200);
DECLARE V_STMT STATEMENT;
DECLARE V_LOAD_STMT STATEMENT;
DECLARE TGT_TABLE_CUR CURSOR WITH HOLD WITH RETURN FOR V_STMT;
DECLARE LOAD_CUR CURSOR FOR V_LOAD_STMT;
DECLARE CONTINUE HANDLER for not_found SET at_end = 1;


-- Create schema
SET stmtSchema = char('CREATE SCHEMA ' concat char(targetSchema));
EXECUTE IMMEDIATE stmtSchema;
SET CURRENT SCHEMA targetSchema;


-- Copy tables and views
SET V_SQL = 'SELECT name, npages FROM SYSIBM.SYSTABLES
        WHERE CREATOR = ''' || trim(sourceSchema) || '''
        AND NAME LIKE ''' || trim(tableNameSelection) || '''
        order by name';
PREPARE V_STMT FROM V_SQL;
OPEN TGT_TABLE_CUR;

fetch_loop:
LOOP
FETCH TGT_TABLE_CUR INTO tableName, numPages;
IF at_end <> 0 THEN
   LEAVE fetch_loop;
ELSE   
   SET stmtTableStructure = 'CREATE TABLE ' ||
       targetSchema || '.' || tableName || ' LIKE ' ||
       sourceSchema || '.' || tableName ;
   EXECUTE IMMEDIATE stmtTableStructure;

   IF numPages > 0 THEN
      call COPY_DATABASE_SCHEMA.copy_table(
              sourceSchema || '.' || tableName,
              targetSchema || '.' || tableName);
   END IF;
END IF;
END LOOP fetch_loop;

CLOSE TGT_TABLE_CUR;
END#

It dynamically issues DB2 SQL commands to create the schema and the tables structure and makes use of the previously created COPY_TABLE to copy the tables content. See the code comments for more information.

To use this just

call COPY_DATABASE_SCHEMA.COPY_DATABASE('originalSchemaName',
          'newBackupSchemaName', '%');

Since I also need to discard old copies, I have created a procedure to drop a schema, including all the tables on it.

/**
*  Drops an entire schema even if it has tables.
*  Views are not supported.
*  @schemaName: the name of the schema to drop
*/
CREATE PROCEDURE COPY_DATABASE_SCHEMA.DROP_SCHEMA(
schemaName VARCHAR(50)
)
LANGUAGE SQL
BEGIN
-- Variables
DECLARE stmtDropSchema VARCHAR(250);
DECLARE stmtDropTable VARCHAR(250);
DECLARE tableName VARCHAR(128);
DECLARE at_end SMALLINT DEFAULT 0;
DECLARE not_found CONDITION FOR SQLSTATE '02000';
DECLARE V_SQL VARCHAR(200);
DECLARE V_STMT STATEMENT;
DECLARE TGT_TABLE_CUR CURSOR WITH RETURN FOR V_STMT;
DECLARE CONTINUE HANDLER for not_found SET at_end = 1;

-- Copy tables and views
SET V_SQL = 'SELECT name FROM SYSIBM.SYSTABLES
   WHERE CREATOR = ''' || trim(schemaName) || '''
   AND CREATOR NOT LIKE ''SYS%''';
PREPARE V_STMT FROM V_SQL;
OPEN TGT_TABLE_CUR;

fetch_loop:
LOOP
    FETCH TGT_TABLE_CUR INTO tableName;
    IF at_end <> 0 THEN LEAVE fetch_loop;
    ELSE
       SET stmtDropTable = 'DROP TABLE ' ||
                   schemaName || '.' || tableName;
       EXECUTE IMMEDIATE stmtDropTable;
    END IF;
END LOOP fetch_loop;

CLOSE TGT_TABLE_CUR;

-- Drop schema
SET stmtDropSchema = char('DROP SCHEMA ' concat
             char(schemaName) concat ' RESTRICT');
EXECUTE IMMEDIATE stmtDropSchema;
END#

This procedures have some limitations, for instance views are not supported.
Nevertheless, it is a good start to all that need to clone a schema or a table.

./M6

Layer Intromission

2009-11-23T13:48:00.011Z

I'm using JTOpen JDBC driver to access AS/400 via DB2.
It works pretty well, but unfortunately it tries to be more than it should be, a JDBC driver that allows a Java application to access a DB2 database.

It interacts with the AS/400 system in a way it should not. For instance, when it's time to change the password, the driver pops-up a notification window stating that it's time to change the password and asks the user if he wishes to do it now.
If this feature seems nice, let me tell you that it is totally wrong!
First, it is a JDBC driver, not an AS/400 system administration application.
Second, this kind of promiscuity among layers has disastrous results.

When one uses a JDBC driver one expects that it operates with the database and nothing else.
When JTOpen starts getting "smart" by interacting with the system, awkward things happen.
For instance, an entire critical system can fail because the driver hang on a "password will expire soon, do you wish to change it now" message and waits for user action instead of doing what it is suppose to do: database work.
Please not that this is not a "password expired" message but a "you must change your password within x days, do you wish to do it now" question.

Here is a real example of such problem: I executed a command line batch which was hold by the JTOpen driver "would you like to change your password now" question.

JTOpen "Would you like to change your password now" User Dialog Box Question.

I got lucky because the command was issued by me, but what if it was issued by a scheduler on a Saturday morning? It would only be noticed Monday morning and a critical job would not have been performed because the JDBC driver messed up.

./M6

iSeries AS/400 Cheat Sheet

2009-11-19T11:36:00.006Z

I am using IBM iSeries AS/400 a lot these days. Since I am not a specialist on such system, I've gathered some simple commands to help me to understand what's going on with my jobs and act on them when necessary.

Here's a simple list of some commands:

Working Active Jobs
Description: shows working active jobs.
Command: wrkactjob

Working Submitted Jobs
Description: shows the list of the working submitted jobs
Command: wrksbmjob

Working Object Lock
Description: shows the locks on an object, like a file.
Command: wrkobjlck (library/object)

CPU Usage Statistics
Description: shows CPU usage statistics, usually filtered to show only resource usages above 2%.
Command: who

Working System Status
Description: shows system overview usagestatus.
Command: wrksyssts

Working Disks Statistics
Description: shows disk usage statistics.
Command: wrkdsksts

Display Message Descriptions
Description: shows detailed information about the messages in a message file.
Command: dspmsgd range(messageId) msgf(library/file)

Display File
Description: shows the contents of a file.
Command: df library/file

Work with Objects
Description: shows a list of names and attributes of specified objects in specified libraries.
Command: wrkobj file

./M6

Hide Warnings in R

2009-11-05T12:23:00.003Z

I've made a presentation about FRBF, an algorithm that I've just implemented in R, and I've used a small trick: I've hidden the warnings.

This is useful for demos and presentations because this way people are not distracted by non-relevant information and they can focus on what is really important.

All that is required is to use options(warn=-1) in the beginning of the script.

./M6

Clear R Console

2009-10-31T10:25:00.002Z

I've been searching for a way to clear the R console, something like a cls() function.
But it seems R does not provide one.
I've found and tried a solution for Windows that emulated the CTRL+L command, which clears the console, but it simply did not work.

So, after some more research I've found this extremely easy, quick and dirty solution: cat(rep("\n",128)).
It does precisely what I need and is system independent.

./M6

Reset Windows and Linux Passwords

2009-10-19T21:46:00.003+01:00

I've just came across a fantastic tool for system administration.
Ever used a system that no one recalls the administration password?
Or have you ever inherited a system that the only person who administrated it retired?

This tool will certainly ease the trouble of resetting the administration password: Kon-Boot.

./M6

Tutorial and Presentation Creation Software

2009-09-25T11:24:00.005+01:00

I've just came across with the best - so far - solution between functionality, quality, export formats and price for tutorial and presentation creation software, including desktop video capture.

This great solution is Wink.
I've tested several solutions like this one before, all usually they all do the same:
capture the screen, compose the frames with some tags or highlight rectangles and export it to a Flash SWF video.
But Wink is different. It does not capture the screen as a simple bitmap, it also captures the objects, like the mouse pointer, and allows to freely specify the frames per second for screen capture and video export.
This allows a much more flexible frame composition, like positioning the mouse cursor on any part of the screen, change its pointer and export the video with comfortable frame per second ratio where the mouse cursor is automatically moved even if it has been positioned on a different location from where it was captured.

./M6

Unix/Linux Cheat Sheets

2009-09-15T09:31:00.003+01:00

I've just found a great collection of several Unix and Linux cheat sheets.
It covers system commands and tools like AWK and SED.
It's the Linux-Unix cheat sheets - The ultimate collection.

./M6

How to Create PDF from LaTeX

2009-09-08T17:34:00.003+01:00

I was using Ghostscript to generate a PDF document written in LaTeX, and I was getting the default red boxes links around the text, which are really ugly.

The search for information about how to remove those red box links returned a very useful document, How to Create PDF from LaTeX.
As the title implies, it is a document that teaches how to create a PDF file from LaTeX, but it covers topics like how to configure the links, which was precisely what I was looking for.

./M6

Algorithms in LaTeX

2009-09-03T16:14:00.006+01:00

I've found this great easy to follow document about algorithms in LaTeX:
The algorithms bundle.

It covers the algorithm and algorithmic environments, the state, comment, loops, conditions and even its customizations.

./M6

Detexify - LaTeX symbol classifier

2009-08-26T16:58:00.005+01:00

I was looking for a LaTeX symbol code when I faced, once more, the problem of taking too much time to find the code for a certain symbol.
LaTeX usually has what one needs, but finding it can take a while.

But this time I got luck. I found Detexify2 - LaTeX symbol classifier which will recognize a handwritten symbol and show the LaTeX corresponding matches.

It worked great for me, and this is now one great tool to have nearby whenever I'm using LaTeX.

./M6

KDE on Windows

2009-08-13T21:17:00.006+01:00

I've just installed the KDE on Windows and my XP is now a happier operating system.

I was looking for Amarok, since that's by far the player I love most, but the release I'm using, 4.3.00, seems not to have it yet.
Nevertheless, I've setup some packages and now I'm able to run things like Kate, Dolphin and KMahjongg .
I love Dolphin as a file manager, since it's philosophy is suited to my needs and usage.
Too bad the Shift+F4 in Dolphin and the terminal command in Kate does not call the DOS box like it calls a terminal in Linux.

This project is not in the final state, so there's not many applications and it can be unsuitable for daily use.
But this is a very cool project and I'll keep an eye on it and, when possible, I'll try to make some changes like using Dolphin, Amarok, Kate and other applications that I prefer to Windows alternatives.

Here's some pictures of some application running on my XP:

Dolphin running on Windows XP

Konqueror running on Windows XP

KWrite running on Windows XP

KDE system settings running on Windows XP

./M6

Reorder columns in R

2009-07-24T23:36:00.003+01:00

I got the need to reorder the column order or a data frame in R and after searching a little, I've found a very easy way to do it.

Having a data frame named test like


    a  b  c  d  e
[1,] 1 11 21 31 41
[2,] 2 12 22 32 42
[3,] 3 13 23 33 43
[4,] 4 14 24 34 44
[5,] 5 15 25 35 45

all that is required is to reassign the data frame using a new column order, like


new_column_order <- c("b", "c", "a", "e", "d")

test <- test[,new_column_order]

And that solves the problem.

This seems to work both with a data frame and a matrix.

./M6

MVC vs. MVP

2009-07-24T11:24:00.002+01:00

I've found an interesting description about Model-View-Presenter and Model-View-Controler and how they differ in StackOverflow: What are MVP and MVC and what is the difference?

./M6

Apollo 11 Source Code on Google Code

2009-07-21T15:53:00.001+01:00

Check Google Code Blog for more info on this.

./M6

10 Apollo-era technologies used today

2009-07-21T14:40:00.002+01:00

The coolest technologies that the moon landing gave us.
See it in Computerworld.

./M6

Free Cheat Sheets for Developers

2009-07-17T17:50:00.002+01:00

Here's a set of free cheat sheets for developers: http://refcardz.dzone.com/
There's lot of information about Drupal, Java Concurrency, Java Server Pages, Maven, JavaFX and a many more.

./M6

Morgan Stanley Report about How Teenagers Consume Media

2009-07-15T10:22:00.002+01:00

Morgan Stanley has released a study made by a 15 year old summer intern, Matthew Robson. Matthew researched about his friends and colleagues habits of media consumption and the results are very interesting, in particular when compared with adult people habits.

How Teenagers Consume Media

./M6

Introduction to the R Programming Environment

2009-07-14T16:34:00.003+01:00

I've found an easy to follow and understand R introduction: An Introduction to the R Programming Environment.

./M6

TomTom Maps are not that Good.

2009-07-13T10:08:00.011+01:00

I have a TomTom One XL GPS. It was a gift, so I did not choose it myself.
It was a great gift and one of the first things I did was to update its map.
After doing it I tried it out.
To my disappointment, it didn't had the street where I live. It just had part of the surrounding neighborhood, so it look like I was in the middle of nowhere, like doing off-road with my car...

TomTom says there's an average of 15% of roads and streets changing every year. The neighborhood where I live was finished in 2001, meaning it has already 8 years.
There were a couple, or so, new TomTom maps that came out but none had my street. Finally, the current version, 8.25, has my street but it comes with an error on its name...

8 years of delay and it came out with an error!...
Unbelievable...

I do know TomTom buys the maps, it does not make them themselves, they get them from Tele Atlas if I'm not mistaken, but I have nothing to do with it. I have a TomTom product, not a Tele Atlas, so it is TomTom who's responsible for the products they sell, even if it includes technology they get from others.

TomTom states it works hard to deliver the ultimate naviagtion experience. The problem is that TomTom fails in the basics: the maps.
And it's not the problem it took 8 years to include my street on its maps, its the fact that the maps need to be cleaned up and you need to know extra information about your destination before you're actually be able to search for your destination:

The street names have errors and are totally unnormalized. For instance, if you're looking for an avenue, you don't know if it starts with "Avenue", "Av." or "Av". Needless to say that if you're looking for street ABC but it's registered in the system as ABB, you'll have trouble to find it. You have to look for all possible combinations and watch out for typos.
It does not allow you to search for middle strings, you always have to search for the beginning of the string. If you're looking for X, and you don't know if it's an avenue, a street or a town square, you're unable to simply search for X, and you fail to find it.
You must know extra information about your destination. For instance, if you need to find destination X on city A, you must provide the X zip code or the civil parish. Needless to say that in many countries, Portugal included, the zip codes have mistakes and people don't always know the name of the civil parish where X is located. If people knew this kind of information, probably they also knew X and would not require TomTom to guide them.

All this combined, I feel frustrated using my TomTom GPS because it does not have, or I'm unable to find, around 20% of my destinations... Talking about "the ultimate navigation experience": do it the hard way, see on a paper map, watch the stars, or stop and ask for directions...

I don't need a search engine running on my TomTom, though it would be extremely helpful, but name normalization and reducing all these search barriers would result on much better search results for the user.

./M6

Subversion Merge Tracking

2009-07-09T15:06:00.004+01:00

If you've been using Subversion (Svn) with branches and had to perform a merge, than you've already screamed in despair just like I've just done.
Svn, up to version 1.5, was unable to perform merge tracking correctly, a major functionality to everyone who has to work with several versions of the same application.

But fortunately, version 1.6 already has merge tracking working correctly.
I already had Svn 1.6 client installed, so all I need to do was upgrade the Debian server to Lenny and the manually upgrade the Svn server to version 1.6.
Everything went well, and there weren't many dependencies needed to be installed manually, so it was even easier than I expected.

Having everything in place, it was time to perform the merge. The merge consisted in including the maintenance branch into the development branch.
This was the second time this kind of merge was going to be performed. Since the previous merge was done without merge tracking, the logs and the graph was kind of useless to know the files history.
Even worst, when the merge was tested, it looked like the first merge had to be repeated. I did not understood this Svn weird behavior and found no reason for it, but there were files that were selected to be merged twice. The first merge was going to happen to the file contained up to revision 2636 and the other merge from revision 2637 up to the Head revision.

It had to be done carefully, but 8 hours later, the merge was done with no problems.

Since this merge was performed with the merge tracking functionality working, now it is possible to automatically track the file evolution. I'm hopping to have a faster, and with less stress, merge in the future.

./M6

Once Accenture. Always Accenture.

2009-07-03T13:13:00.007+01:00

Yesterday I attended to Accenture Alumni cocktail party.
It was an event exclusively for former Accenture employees and, obviously, for Accenture Senior Managers and above.

I've been with Accenture twice, and loved it both times.
I always felt that Accenture really care about its people. The proof is in such meetings, Accenture cares about you even if you're no longer with them.
The event itself was very nice and allowed us to chat with people that we haven't seen for awhile. Many of us updated the mobile numbers between two drinks, sushi and ice cream.

Obviously such events have a business return. There were a lot of business cards changing hands, contacts updated and new contacts made.
There's also the marketing part of it, people that attended surely chatted about it with current coworkers or write about it in their blogs.
And precisely how many companies do you know that invite former employees for a cocktail?

On the way out, everybody got a Bonsai with a "thank you" card for helping Accenture to be the company that it is.

Well, tank you Accenture for the cocktail and for the challenges that I was given and that allowed me to be a better professional.
./M6

Gimp and .eps Files

2009-06-29T21:52:00.002+01:00

I use Gimp on all systems and I've some Encapsulated PostScript (.eps) files on Windows that I need to open and edit. In order to Gimp on Windows open .eps files, it requires Ghostscript to be in your system.

Here's how to do it:

Download and install Gimp;
Download and install Ghostscript
Setup the environment variable GS_PROG to the Ghostscript executable file, like C:\Program Files\gs\gs8.64\bin\gswin32.exe.

Now Gimp should be abble to open EPS files.

./M6

JFace TreeView with Manual Expand of TreeItems

2009-06-29T18:07:00.015+01:00

I have a FilteredTree with check items and I was trying to expand the tree whenever the user checks an item on it. By default, the tree does only expand a TreeItem when the user clicks on the + icon and retracts when the user clicks on the - icon.
Since this tree has check items, I wanted the tree to expand when the user clicks on the check box.

This proved to be a lot harder than I expected, partially because I was using the wrong object, partially because it is lazy, and partially because it was hard to find an answer for what I was doing wrong.
So, I'm posting here how to manually expand a TreeView, which is part of a FilteredTree.

To begin with, the TreeView requires the following classes to be defined:

1. Your tree node that will hold the data of each tree item:

private class Node {

private final Node parent;
private final String word;
private List children = new ArrayList();

Node(Node parent, String word) {
this.parent = parent;
this.word = word;
if(parent != null) {
  parent.children.add(this);
}
}

public Node getParent() {
return parent;
}

public Collection getChildren() {
return new ArrayList(children);
}

public boolean hasChildren() {
return children.size() > 0;
}

public void setChildren(Collection newChildren) {
if(newChildren != null) {
  children = new ArrayList(newChildren);
}
}

public String getWord() {
return word;
}

}

Please note that this class can be whatever class you require, this is only an example.

2. A tree content provider that will provide the content for the tree:

private class NodeContentProvider implements ITreeContentProvider {

@Override
public Object[] getChildren(Object element) {
return ((Node)element).getChildren().toArray();
}

@Override
public Object getParent(Object element) {
return ((Node)element).getParent();
}

@Override
public boolean hasChildren(Object element) {
return ((Node)element).hasChildren();
}

@Override
public Object[] getElements(Object inputElement) {
return (Object[]) inputElement;
}

@Override
public void dispose() {
// unused
}

@Override
public void inputChanged(Viewer viewer, Object oldInput,
Object newInput) {
// unused
}

}

3. The label provider that will provide the label for each item in the tree:

private class NodeLabelProvider extends LabelProvider {

private final TreeViewer viewer;

NodeLabelProvider(TreeViewer viewer) {
this.viewer = viewer;
}

@Override
public String getText(Object element) {
Node node = (Node) element;
return node.getWord();
}
}

I'll create a FilteredTree, but since it makes use of TreeView, using only a TreeView is trivial:


PatternFilter patternFilter = new PatternFilter();
FilteredTree filteredTree = new FilteredTree(cTree,
   SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL | SWT.CHECK,
   this.patternFilter);
filteredTree.setInitialText("type your filter text here");
TreeViewer treeViewer = filteredTree.getViewer();

// Assign the label provider
treeViewer.setLabelProvider(new NodeLabelProvider());

// Assign the content provider
treeViewer.setContentProvider(new NodeContentProvider());

// Populate the tree with elements
Node ex1= new Node(null, "Example 1");
new Node(ex1, "Example 1.1");
new Node(ex1, "Example 1.2");
new Node(ex1, "Example 1.3");
Node ex2= new Node(null, "Example 2");
new Node(ex2, "Example 2.1");
Node[] nodes = Node[] {ex1, ex2}
viewer.setInput(nodes);

// Event for item selection
treeViewer.getTree().addListener(SWT.Selection, new Listener() {
public void handleEvent(Event event) {
  TreeItem item = (TreeItem) event.item;
  Node node = (Node)item.getData();
  // Manually Expand
  treeViewer.expandToLevel(node, 1);
  treeViewer.update(node, null);
}
});

Please note that the tree selection event always expands the selected node, you may wish to retract it or do another operation, like check all its descendants.
This is actually quite simple, but I was calling treeViewer.expandToLevel with the TreeItem instead of using the Node object, and that was the cause of my problems.

If you're looking for a similar example but using custom images, check Eclipse Nuggets.
./M6

Mediocrity is a choice

2009-06-20T15:26:00.003+01:00

As Seth Godin states on a small post, quality is the result of choices one get to make every day.
Here's the full post: On the road to mediocrity.

./M6

Success is a Continuous Journey

2009-06-17T15:36:00.004+01:00

Business success is a continuous journey, not a destination. I've learned this long ago, but I couldn't say it better than Richard St. John:

It's not about falling, it's about getting up again...

./M6

RCP save workbench status

2009-06-16T18:06:00.004+01:00

In Rich Client Platform (RCP) application, the workbench status can be easily saved and restored by simply including the snippet bellow in the ApplicationWorkbenchAdvisor class, that extends WorkbenchAdvisor.


@Override
public void initialize(IWorkbenchConfigurer configurer) {
super.initialize(configurer);

// tell eclipse to save workbench state when it quits
// (things like window size, view layout, etc.)
configurer.setSaveAndRestore(true);
}

This will automatically save the status of the workbench when the application is closed and will automatically restore that status when the application is executed again. The settings are saved on the [runtime-{your-product}]/.metadata/.plugins/org.eclipse.ui.workbench/workbench.xml file.

./M6

Selecting a value from a SWT CCombo on RCP

2009-06-16T11:23:00.007+01:00

It looks like the CCombo custom SWT object lacks some selection functionality. I'm using a CCombo as a table cell editor on my Rich Client Platform (RCP) application and I've found out that it is (almost) impossible to detect the user selection with both the keyboard and the mouse.

The selection listener does not work as expected. Documentation says:

the widgetSelected method is triggered whenever a selection occurs in the control, i.e. when the user browses the option list this event is triggered;
the widgetDefaultSelected method is triggered when default selection occurs in the control, i.e. when the user selects an option from the list this event is triggered.

One might think, as I thought, that all one has to do is to catch the widgetDefaultSelected event and one would know which option the user has selected from the list.
This is only true when the user performs the selection using the keyboard, i.e. after browsing through the options list the Enter/Return key is pressed.
If the user decides to use the mouse, the widgetDefaultSelected event is not triggered at all, but widgetSelected is.

I though I could detect the user selection with the mouse listener. I was wrong. After trying a couple more possibilities, it turns out there's no (easy) way to detect if the user has performed a selection using the mouse...

So I had to do a workaround for it. Since the widgetSelected is triggered by the mouse clicks, I tried to use that event. Unfortunately the event has no real useful information, like if it was triggered by a right button mouse click. But fortunately, the CCombo object does have a couple of methods that allowed to infer that a selection has been made. In particular, it has a method to check if the options list is visible or not. Since a selection with the mouse makes the options list disappear, I've used it.

Here's the snippet:


// Selections events
combo.addSelectionListener(new SelectionAdapter() {
 // Selection changed, check if the options are still visible
 public void widgetSelected(SelectionEvent e) {
   // If list is not visible assume that the user has
   // performed selection with the mouse
   if (!combo.getListVisible()) {
       setEditionValue(combo);
   }
 }

 // Option selected
 public void widgetDefaultSelected(SelectionEvent e) {
   // User performed a selection with the keyboard
   setEditionValue(combo);
 }
});

This is not a perfect solution, it's a workaround, but it's working just fine for me.

./M6

Current time as numeric value in R

2009-06-13T14:22:00.003+01:00

To get the current time, just use the Sys.time() function, see the Sys package for more information.
To get the current time as a numeric value in R, just use unclass(Sys.time()).
This seems to be higher accurate, 0.01 seconds.

./M6

tofrodos package

2009-06-13T12:12:00.004+01:00

Kubuntu does no longer has the "old" DOS tools. I needed to use the dos2unix command and I found out it was no longer part of the standard core installation. Obviously it's still available, so all I had to do was install the tofrodos package, just sudo apt-get install tofrodos and the problem is solved.

./M6

R Package with S4 Objects

2009-06-03T15:05:00.015+01:00

I've finished the development of the (beta version) clustering algorithm on R for my MSc thesis and I'm releasing it for tests.

I've developed it mainly in Windows, but when it comes to the packaging part, I've switched to Linux. This is mainly because R packaging in Windows implies to install a lot of base Linux applications and tools on Windows. For those that wish to go that road, here's what you have to do: read Making tutorial about R Packages Under Windows: A Tutorial by Peter Rossi.
For everyone else, just boot your Linux.

Before I start, I took a look at Writting R Extensions. This is the first step for all that wish to build an R extension. A fast and easy way to know how to pack, is to read the An Introduction to the R package mechanism.

My implementation uses S4 objects, and that was a problem, since I had all kinds of warnings and errors during the package tests and installation. Here's the transcriptions of the post I've sent to the R-Help list asking for help:

Here's what I do:

*1.* in R console, I do and get:
> package.skeleton(name='remora')remora-package
Creating directories ...
Creating DESCRIPTION ...
Creating Read-and-delete-me ...
Saving functions and data ...
Making help files ...
Done.
Further steps are described in './remora/Read-and-delete-me'.
Warning messages:
1: In dump(internalObjs, file = file.path(code_dir,
sprintf("%s-internal.R",  :
deparse of an S4 object will not be
source()able
2: In dump(internalObjs, file = file.path(code_dir,
sprintf("%s-internal.R",  :
deparse of an S4 object will not be
source()able
3: In dump(internalObjs, file = file.path(code_dir,
sprintf("%s-internal.R",  :
deparse of an S4 object will not be
source()able
4: In dump(internalObjs, file = file.path(code_dir,
sprintf("%s-internal.R",  :
deparse of an S4 object will not be source()able


I don't know why I get these warnings. I've followed R
implementation rules and the S4 objects work fine.


*2.* Performing the 'R CMD build remora' command I get:

* checking for file 'remora/DESCRIPTION' ... OK
* preparing 'remora':
* checking DESCRIPTION meta-information ... OK
* removing junk files
* checking for LF line-endings in source and make files
* checking for empty or unneeded directories
* building 'remora_1.0.tar.gz'

And the remora_1.0.tar.gz file seems ok.

*
3.* Performing the 'R CMD check remora' command I get:

* checking for working pdflatex ...sh: pdflatex: not found
NO
* checking for working latex ...sh: latex: not found
NO
* using log directory '/home/fmm/thesis/R/src/remora.Rcheck'
* using R version 2.8.1 (2008-12-22)
* using session charset: UTF-8
* checking for file 'remora/DESCRIPTION' ... OK
* checking extension type ... Package
* this is package 'remora' version '1.0'
* checking package dependencies ... OK
* checking if this is a source package ... OK
* checking for executable files ... OK
* checking whether package 'remora' can be installed ...
ERROR
Installation failed.
See '/home/fmm/thesis/R/src/remora.Rcheck/00install.out'
for details.

*4.* the log file contains:

* Installing *source* package 'remora'
...
**
R

**
data

** preparing package for lazy
loading
Error in parse(n = -1, file = file) : unexpected '<' at 745:
`.__C__remoraConfiguration` <- 746: <> -> code2LazyLoadDB
-> sys.source -> parse Execution halted
ERROR: lazy loading failed for package
'remora'
** Removing
'/home/fmm/thesis/R/src/remora.Rcheck/remora'
fmm@Darkmaster:~/thesis/R/src$ grep -i __C__remoraConfiguration *
fmm@Darkmaster:~/thesis/R/src$ grep -i __C__remoraConfiguration */*
remora.Rcheck/00install.out:745: `.__C__remoraConfiguration`
<- remoraConfiguration is a constructor for the
remoraConfiguration S4 object.  
# # Class configuration definition.
# CLASS_REMORA_CONFIGURATION <- "remoraConfiguration" class_configuration
<- setClass(CLASS_REMORA_CONFIGURATION, representation(
number_clusters = "numeric", class_name = "character",
weighting_function="character", scale_variance="logical", s="numeric",
d="numeric", alfa="numeric", eta = "numeric", niter="numeric",
niter_changes="numeric", perform_sum="logical", verbose="logical"),
prototype = list(number_clusters=numeric(), class_name=character(),
weighting_function=character(),    scale_variance=logical(),
s=numeric(), d=numeric(), alfa=numeric(), eta=numeric(), niter=numeric(),
niter_changes=numeric(), perform_sum=logical(), verbose=logical())) 
# # Builds a Remora configuration object.
# # [...]
# remoraConfiguration <- function(number_clusters, class_name,
weighting_function = FUNCTION_REMORA_EUCLIDEAN,
scale_variance=TRUE, s_value = 0.001, d = 0.3, alfa = 0.9, eta = 0.01,
niter=-1, niter_changes=5, perform_sum = TRUE, verbose=FALSE)
{  
 result_configuration <- new(CLASS_REMORA_CONFIGURATION) 
 [...]  
 result_configuration
}

But, unfortunately, no help came from there...
I've never stopped the search for the answer, and I've finally found it. It's actually quite easy.
Instead of packing it from the current environment, I've just passed the package.skeleton the list of source files to build the package. Here's the small R script I've done to automate the packaging procedure for my "Remora" package:


cat('\nPacking Remora...\n')

file_lst <- character(5)
file_lst[1] <- '/home/m6/thesis/R/src/1_classes.r'
file_lst[2] <- '/home/m6/thesis/R/src/2_common.r'
file_lst[3] <- '/home/m6/thesis/R/src/3_model.r'
file_lst[4] <- '/home/m6/thesis/R/src/4_predict.r'
file_lst[5] <- '/home/m6/thesis/R/src/5_main.r'   

package.skeleton(name = "remora", force = TRUE, namespace = TRUE,
code_files = file_lst)   

cat('\nDone.\n')

Now it's time to go to the directory created, with the name of the package, from now on {package}, and edit the following files:

{package}/DESCRIPTION, the description of the package;
{package}/NAMESPACE, the list of functions and classes to export to the user;
{package}/man/{package}-package.Rd, the package help file, the \examples section must provide executable code, since R check command will execute this code;
{package}/man/{class_name}-class.Rd, the classes help files;
{package}/man/{function_name}.Rd, the functions help files;

All files under /man/ are tex files and will be compiled to provide the functions help when invoked by the user.
It's only necessary to document the classes and functions that will be exported, i. e. exported in the NAMESPACE file, since all the others will not be visible to the user. All the other .Rd files may be deleted.

After the package has been created, I've tested with the "R CMD check {package}" command. My package name is "remora", so my command was "sudo R CMD check remora".
I had to run this command with the administration role, so I prefixed it with the "sudo" command. I believe this is a characteristic of the Kubuntu distribution.

Finally I've build the package with the "R CMD build {package}" command that created the tar.gz file for distribution.

To install it, just use the "R CMD INSTALL {package}" command. I've entered R and it worked fine.
To uninstall just execute "R CMD REMOVE {package}".

./M6

Bing

2009-06-01T11:56:00.007+01:00

But It's Not Google.
That's Bing, the Microsoft rebranded and reformated search engine.

Bing has a nice background picture and allows me to search in English or Portuguese, but when there's a tie, the Portuguese result shows up first.

For what I could tell, it's definitely not Google.
Google is currently more than a search engine.
On Google I can ask simple questions like "4 times 5" or "1 euro in usd" and I get "4 times 5 = 20" and "1 Euro = 1.4225 U.S. dollars", this one depending on near real time
In Bing I only get regular search engine results.

Bing answer for 4 times 5.

When trying to search information in news group "linux.debian.laptop", I can do it in Google and since Bing knows it, Bing shows the Google Groups for "linux.debian.laptop".

As Seth Godin puts it, looks like Microsoft is trying to be the next Google, but currently here's already a next Google: Google.

Why should people change for something that works well to something that seems not to have a real distinguishing factor? At least for now, it's still, as alomost in Google, a Beta version. Even if Microsoft adds a few cool features, how much time it Google take to clone it and improve it?

I don't really know why Microsoft is investing so much time, money and effort in such a battle when they could be doing something remarkable.

Update
I've just discovered that actually Bing does some math and it knows how to answer 4 times 5.

What I also discovered is that, like many Microsoft applications, it thinks it knows what is best for me and, as always, it thinks wrong!
I've specifically have told Bing that I wanted results in English, but it ignored me and gave me results in Portuguese and looks like in Portuguese it was unable to compute 4 times 5.
Looks like Bing thinks that since I'm located in Portugal, I cannot ask questions in English! Is this stupid or what?
If it thinks it's smart enough to know what's best for me, I've asked the same question in Portuguese, "4 vezes 5" and, as I expected, it failed to answer the question.
Not very smart, Bing...

Bing is not Google, and they can say that again!
Keep up like that and definitely it will continue to live obfuscated by Google, like the "eternal wanna be"...

./M6

Java by API examples

2009-05-28T15:41:00.004+01:00

I was seeking information for the FilteredTree Jface object and I've found a great knowledge repository for Java, SWT, JFace EJB, and other technologies, like C#, C++, Python, SQL Server, and many more.

In the Java By API examples, everything is by example and it's hierarchically organized, which helps a lot when one's exploring Java packages, for instance.

You can take a look at it in http://www.java2s.com/.

./M6