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Orange Canvas examples

A place to ask questions about methods in Orange and how they are used and other general support.

Orange Canvas examples

Postby mrt » Wed Mar 27, 2013 8:21

I recently discovered "Orange Canvas" and at first it seemed to be the tool I have been searching for my data analysis/manipulation needs. Now, after a few days tinkering around with it, I feel a little frustrated.

The few tutorials I found around net and this site seem to be mostly script oriented or really brief. I found three tutorial ows files from .../Orange/OrangeCanvas/application/tutorials folder but I seem to be missing some widgets to open them ( although I have installed all the add-ons.

What would really help me is if I could find some example Orange Widget Schemas where I could study how to use "python script" widgets and/or multitarget widgets properly. It seems I am missing some general logic how to use them. I can use simple widgets like, load the data, visualize it in data table or scatter plots, use the feature constructor, etc but have failed to get "python script" and "neural network" widgets working.

I have allready read:, and searched the forums here/google.


Re: Orange Canvas examples

Postby ubershmekel » Wed Mar 27, 2013 15:16

Here's my canvas.

And here is an example python script

Code: Select all
sl_id_index = in_data.domain.index('slide_id')
diagnosis_index = in_data.domain.index('diagnosis')
out_data =

for i, row in reversed(list(enumerate(in_data))):
    sl_id = row[sl_id_index].value
    if row[diagnosis_index] != 'negative':
        #out_data[i][diagnosis_index] = 'falciparum'
    if sl_id in bad_slides:
        del out_data[i]

print 'in, out', len(in_data), len(out_data)

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