Whitening: functional or in place?

[clementfarabet]

First thanks for the whitening functions in whitening.lua. This is very useful.

One question/concern: these functions currently replace the data that's passed in by the whitened (or coloured) data. Is this the expected behavior? I think that it's probably better to leave the input data untouched. What do you think?

[andreirusu]

Hi Clement,

You are right, and the intended behavior was not to modify input data. I cloned the input data into auxdata in all whitening functions; then I've updated auxdata in place and returned it; will this not achieve the desired behavior?

Cheers, Andrei

[clementfarabet]

Hi Andrei, I spoke too fast: the problem only occurs in the colourize functions, there: zca_colour and pca_colour. zca_whiten and pca_whiten are correct.

[andreirusu]

Good catch, that was a bug! I've fixed it and I've issued a pull request. Thanks!

Andrei

[clementfarabet]

Cool, thanks for the fix! I've merged it.