jcamp-dx on Maven Central

…and the artifacts (legacy and first maven-based release) are on Maven Central:


Still impressed by the quick resolution of requests over at sonatype. :-)

Posted on September 4, 2014 at 5:10 pm by fracpete · Permalink · Leave a comment
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Libraries that are essential to ones own projects, but no longer maintained, can be annoying. Today was just another occasion, where I forked an existing library and upgraded/fixed it. This time, the library jcamp-dx is for reading spectral data files.

The original project is hosted on sourceforge.net:

The new home of the project (and also mavenized) is here:

As soon as the project has been approved for Maven Central, I’ll be deploying legacy and new artifacts. :-)

Posted on September 2, 2014 at 3:27 pm by fracpete · Permalink · Leave a comment
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If you feel like your vim/gvim needs sprucing up a bit, how about giving it a nice informative line at the bottom of the screen, using vim-airline:


Posted on August 20, 2014 at 12:50 pm by fracpete · Permalink · Leave a comment
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Maintenance release for collective-classification

Just made a new maintenance release available for the collective-classification project: it now works with Weka 3.7.11. You can download the Weka package from here:


Posted on August 20, 2014 at 10:40 am by fracpete · Permalink · Leave a comment
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Plant Protection Society Presentation

Earlier this year, I got invited to give a talk at the Plant Protection Society Symposium titled The plant protection data toolbox: On beyond t, F and χ, thanks to my expertise in data mining.
Despite me drawing the short straw in getting the last slot for the day – right before drinks and nibbles – my talk was well received. I did various analyses of an aphid-related dataset and also showed briefly a project that I’m working on with Cropwatch BV in regards to insect classification – all using ADAMS/WEKA, of course. Generated a few interesting conversations after my talk, which was really great.
The only downside was getting up at 5am and getting back home by 10pm… But well worth it!

Posted on August 11, 2014 at 8:57 pm by fracpete · Permalink · Leave a comment
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Visualizing confusion matrices

I always wanted to be able to visualize large confusion matrices as a heatmap. Making it easier to visualize where misclassifications hot spots are. Hence I started another plugin project for the Weka Explorer


It offers, at the moment, the following visualizations:

Here is an example of the heatmap visualization, using the matrix generated by J48 on the UCI dataset optdigits:


Posted on August 5, 2014 at 4:23 pm by fracpete · Permalink · Leave a comment
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Tree visualization

On the weekend, I was working on a paper and wanted to have nice diagrams of J48 trees. However, the default visualization in Weka is anything but great looking. Due to lack of Java libraries, I hacked together a little plugin for the Explorer that allows you to use the GraphViz executable dot to generate and display an image:


You can install a release using Weka’s package manager.

Here is an example J48 tree generated for the UCI dataset iris:

Posted on August 5, 2014 at 2:25 pm by fracpete · Permalink · Leave a comment
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Stopwords for Weka

Stopwords support in Weka have always been a bit poor, to say the least. Initially, there was only a hard coded list, based on the Rainbow tool. However, simply having stopwords for the English language was a bit limited. Being able to supply your own list of stopwords in the StringToWordVector filter made the whole thing already a bit more flexible. But, you still couldn’t supply your own stopwords algorithm. Yesterday, I sat down and implemented a new class hierarchy centered around the weka.core.stopwords.StopwordsHandler interface. I added the following algorithms:

Eibe reworked the StringToWordVector filter today to make use of the new class hierarchy.

Posted on July 21, 2014 at 12:46 pm by fracpete · Permalink · Leave a comment
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python-weka-wrapper 0.1.8 released

Today, I released a new version of the python-weka-wrapper library: 0.1.8.
No new functionality, apart from being able to create Instance objects using Python lists as well rather than just Numpy arrays, just bugfixes: the scatterplot for datasets and the installer were broken.

Posted on June 26, 2014 at 11:00 pm by fracpete · Permalink · Leave a comment
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JFileChooser-Bookmarks project launched

Last year, while working on a consulting project, I had to export lots of screenshots from ADAMS. I got so annoyed at constantly having to click through my directory hierarchy, that I implemented a little accessory component for the JFileChooser in Swing, allowing me to define bookmarks. Man, that made it so much easier all of a sudden!

The component is modeled after the bookmarks from the file chooser that Gnome users have been familiar with for many years. Here is a screenshot:


You can find the project homepage here:

And on Maven Central:

Posted on June 26, 2014 at 9:09 am by fracpete · Permalink · One Comment
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