[Numpy-discussion] behavior of 'insert' for inserting multiple values

[Stéfan van der Walt]

Hi Mark

2008/5/27 mark <markbak@gmail.com>:
>>>> a = arange(5.)
>>>> insert(a,3,[7,7])
> array([ 0.,  1.,  2.,  7.,  3.,  4.])
>
> But insert only inserts one of the 7's, while I want both values to be
> inserted. Nor does numpy throw a warning (which I think would be
> appropriate). The way that works correctly is
>
>>>> insert(a,[3,3],[7,7])
> array([ 0.,  1.,  2.,  7.,  7.,  3.,  4.])

You need to specify two insertion positions, i.e.

np.insert(a, [3, 3], [7, 7])

I think we should consider a special case for your example, though.

Regards
Stéfan