This is true at the Python level and is not related to numpy. "x=c[2,3]" is equivalent to "x=c.__getitem__((2,3))".  Note that the index pair is passed as a tuple. On the other hand, a single index is not passed as a tuple, but is instead passed as is. For example: "x = c[a]" gets passed as "x=c.__getitem__(a)". If 'a' happens to be '(2,3)' you get the behavior above.

So, although lists and arrays can be used for "fancy-indexing", tuples cannot be since you can't tell the difference between a tuple of indices and multiple indices inside square brackets.


[SNIP]