CPA classifier error

Hello CellProfiler team

When I try to classify the objects after training in the classifier I get this error message

An error occurred in the program:
IndexError: list index out of range

Traceback (most recent call last):
File “classifier.pyc”, line 1043, in ScoreAll
File “fastgentleboosting.pyc”, line 152, in PerImageCounts
File “multiclasssql.pyc”, line 214, in PerImageCounts
File “multiclasssql.pyc”, line 181, in do_by_steps
File “multiclasssql.pyc”, line 164, in where_clauses

and CPA freeze.
Running the CPA classifier example without any problem. So I guess there is something wrong with my dataset?

Thanks for your help


Hi Bertrand,

This could be a number of things. First, please see this thread for some ideas: viewtopic.php?f=12&t=1381&p=5503&hilit=multiclasssql#p5503

Possible problems:

  • Are there any NANs (or other “odd” characters, e.g. scientific notation) in your database?
  • Are you only using a couple of images and/or objects to classify?

If you are still having trouble, please post your properties file and the pipeline .cp file. We may be able to see something wrong.