[pymvpa] NFoldSplitter question

[Michael Hanke]

Hi,

On Wed, Mar 04, 2009 at 02:54:57PM +0100, Susanne Greiner wrote:
> Splitter generated 6 splits
> expected: 10
> ----
> Why is the number of splits lower than the expected number of
> all combinations? (should be equal according to the docstring)
> Note that we are using latest tarballs of Numpy, PyMVPA etc.

What can I say -- it looks like a bug.

The function that does it is getUniqueLengthNCombinations() in
mvpa.misc.support. It looks like it is broken for k>2. Never done that
before and hence never noticed. Thanks for spotting.


However, that function operates recursively and my blood-sugar level is
too low for combinatorics and recursive function together -- need some food
first...


Michael

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