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Concatenation of columns in Canvas?

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Concatenation of columns in Canvas?

Postby PenguinJunk » Fri Apr 12, 2013 14:02

I'm just trying Orange for the first time. I'm happy to script in Python but I rather like the visual aspects of Orange Canvas. However, I'm finding myself rather thwarted by being unable to concatenate column-wise. Have I missed something?

For instance, my data contain observation identifiers alongside attributes. I don't want the identifiers to be used in, say, a k-means clustering so I used Select Attributes to select only the desired attributes. At the end of my work I'd like to join up the observation identifiers to the resulting clusters so that I know to which cluster each observation belongs.

This seems like rather a basic requirement so I'm sure I've missed something. Can anyone help, please?

Re: Concatenation of columns in Canvas?

Postby marko » Fri Apr 12, 2013 16:00

For your use case just make identifiers a meta attribute "Select attributes" widget. Meta attributes are not considered in analyses.

For concatenation try "Merge data", but to use this widgets you will need an identifier attribute in both data sets.

Re: Concatenation of columns in Canvas?

Postby PenguinJunk » Fri Apr 12, 2013 16:24

Brilliant, thank you!

Re: Concatenation of columns in Canvas?

Postby PenguinJunk » Fri Apr 12, 2013 16:38

Hmm, replied too fast. How do I bring back my meta attributes? They are not in the output from the kmeans (actually I'm using PCA at the mo, but I assume this is the same). So still don't have the observation identities with the output. In this case I want to match up my training data with some verification data. Do I have to have all the data in one input to start off with?

Re: Concatenation of columns in Canvas?

Postby Ales » Mon Apr 15, 2013 9:56

Unfortunately PCA strips the meta attributes from the input (but k-Means does not).
I guess this is a bug in PCA. I will fix this.

Re: Concatenation of columns in Canvas?

Postby Ales » Wed Apr 17, 2013 11:25

PCA widget in the current build should now preserve the meta attributes. Can you try it?

Re: Concatenation of columns in Canvas?

Postby PenguinJunk » Thu Apr 18, 2013 11:41

Yes it does! Thank you for such a quick response.


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