index objects are not broadcastable to a single shape
This must be up there with the most useless confusing error messages:
a=numpy.array([1,2,3]) b=numpy.array([1,2,3,4]) a*b Traceback (most recent call last): File "<stdin>", line 1, in ? ValueError: index objects are not broadcastable to a single shape
Simon. -- Simon Burton, B.Sc. Licensed PO Box 8066 ANU Canberra 2601 Australia Ph. 61 02 6249 6940 http://arrowtheory.com
Simon Burton wrote:
This must be up there with the most useless confusing error messages:
a=numpy.array([1,2,3]) b=numpy.array([1,2,3,4]) a*b
Traceback (most recent call last): File "<stdin>", line 1, in ? ValueError: index objects are not broadcastable to a single shape
The problem with these error messages is that some code is used in a wide-variety of circumstances. The original error message was conceived in thinking about the application of the code to one circumstance while this particular error is occurring in a different one. The standard behavior is to just propagate the error up. Better error messages means catching a lot more errors and special-casing error messages. It can be done, but it's tedious work. -Travis
On Wed, 12 Apr 2006 19:29:10 -0600 Travis Oliphant <oliphant@ee.byu.edu> wrote:
The problem with these error messages is that some code is used in a wide-variety of circumstances. The original error message was conceived in thinking about the application of the code to one circumstance while this particular error is occurring in a different one.
The standard behavior is to just propagate the error up. Better error messages means catching a lot more errors and special-casing error messages. It can be done, but it's tedious work.
OK. Can the error message be a little more generic, longer, etc. ? "shape mismatch (index objects are not broadcastable to a single shape)" ? I don't know either. I'm just thinking about all the new numpy/python users at work here that I will need to hand hold. Error messages like this are pretty scary. Simon. -- Simon Burton, B.Sc. Licensed PO Box 8066 ANU Canberra 2601 Australia Ph. 61 02 6249 6940 http://arrowtheory.com
Simon Burton wrote:
On Wed, 12 Apr 2006 19:29:10 -0600 Travis Oliphant <oliphant@ee.byu.edu> wrote:
The problem with these error messages is that some code is used in a wide-variety of circumstances. The original error message was conceived in thinking about the application of the code to one circumstance while this particular error is occurring in a different one.
The standard behavior is to just propagate the error up. Better error messages means catching a lot more errors and special-casing error messages. It can be done, but it's tedious work.
OK. Can the error message be a little more generic, longer, etc. ?
Absolutely, I should have finished the above message with an appeal for more helpful generic messages. All suggestions are welcome.
"shape mismatch (index objects are not broadcastable to a single shape)" ?
Definitely better. I would probably drop the index qualifier as well. Thanks for the tip. -Travis
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Travis Oliphant