On Mon, Dec 13, 2010 at 4:53 PM, Keith Goodman <kwgoodman@gmail.com> wrote:
On Mon, Dec 13, 2010 at 12:20 PM, Bruce Southey <bsouthey@gmail.com> wrote:
Unless something has changed since the docstring was written, this is probably an inherited 'bug' from np.mean() as the author expected that the docstring of mean was correct. For my 'old' 2.0 dev version:
>>> np.mean( np.array([[0,1,2,3,4,5]], dtype='float32'), axis=1).dtype dtype('float32') >>> np.mean( np.array([[0,1,2,3,4,5]], dtype='float32')).dtype dtype('float64')
Are you saying the bug is in the doc string, the output, or both? I think it is both; I expect the second result above to be float32.
This was a surprise to me as this 'misunderstanding' goes back to at least numpy 1.1. Both! The documentation is wrong when using axis argument. There is a bug because the output should be the same dtype for all possible axis values - which should be a ticket regardless. The recent half-float dtype or if users want the lower precision suggests that it might be a good time to ensure the 'correct' option is used (whatever that is). Bruce