[Numpy-discussion] Finding values in an array

[Julian Taylor]

On 28.11.2014 04:15, Alexander Belopolsky wrote:
> I probably miss something very basic, but how given two arrays a and b,
> can I find positions in a where elements of b are located?  If a were
> sorted, I could use searchsorted, but I don't want to get valid
> positions for elements that are not in a.  In my case, a has unique
> elements, but in the general case I would accept the first match.  In
> other words, I am looking for an array analog of list.index() method.

np.where(np.in1d(a, b))