PCA Apply error: Matrix inner dimensions must agree

KNIME Analytics Platform
#1

Hi!

I can't say why, but for some data sets I get an error while using "PCA Apply" node:

ERROR     PCA Apply     Execute failed: Matrix inner dimensions must agree.

 

I can't find any documentation for that. Meanwhile the regular PCA node works without problems...

 

Could it be a bug or the data set is wrong?

#2

Hello, 

I can't guess what the problem might be from that error message, would it be possible to see an example?  

Regards,

Aaron

#3

Hi,

I've preapred a reduced dataset, where the problem still exists. I'm also attaching the (simple) workflow screenshot where this error occurs.

Thanks,

Filip

#4

Hi Fillip, 

Thanks a lot for the simple example, it made reprodcuing the problem easy.

Just a hint that may lead to a temporary workaround...If you restrict your analysis to the first 3 parameters, the problem is still apparent.  If you subsequently remove param1, which is all -1s, things start working as expected.  It seems that for some reason this column (and others in the file) are causing the problem.

I'll post back here as soon as I know more.

Regards,

Aaron

#5

Hi Aaron,

Thank you very much!

Regards,

Filip

 

EDIT: As a temporary workaround I've applied low variance filter to eliminate all columns with constant (-1) values and it now works fine.

EDIT2: Above workaround doesn't always work...

#6

Hi,

I'm attaching another, reduced data set which also causes the problem. There is no longer "-1" columns there.

Maybe it could help you to solve the problem,

Regards,

Filip