This line created the data files in the PreProcData/Cifar10/ subdirectory
553MB rgbwhiten_train.t7
123MB rgbwhiten_test.t7
61MB rgbwhiten_valid.t7
only these three files were created, and then the program hanged on this line forever (hours).
So far I traced it to the call to unsup.pcacov() in Data.lua. This is where it stopped to progress.
I tried to send messages using io.stderr:write() before and after this line of code. The message before appeared on the screen but the message after never showed up.
Any ideas on how to fix it? Thank you!