Dear Sulantha,

Sorry for the delay in response. I somehow missed this email. There seems to be an issue with a call to the function "inv". This function does return two outputs, but here it complains it has only one. My first guess is that you have a function called "inv" that supersede the regular matlab/octave command. Try to type:

which int

If this points to a function in your own libraries, that's the problem. All you need to do then is to make sure that when you run a NIAK pipeline, only NIAK is loaded in the matlab/octave search path. You may also want to consider renaming this function to avoid future trouble. 

If that's not the problem, please provide the version number of octave or matlab, as well as the system that you use. 

I hope this helps. Best regards,

Pierre