[Numpy-discussion] Array2 subset of array1

[Nathaniel Smith]

On Tue, Aug 5, 2014 at 1:58 PM, Jurgens de Bruin <debruinjj at gmail.com> wrote:
> Hi,
>
> I am new to numpy so any help would be greatly appreciated.
>
> I have two arrays:
>
>     array1 = np.arange(1,100+1)
>     array2 = np.arange(1,50+1)
>
> How can I calculate/determine if array2 is a subset of array1 (falls within
> array 1)
>
> Something like : array2 in array1 = TRUE for the case above.

Does this work?
  np.in1d(array2, array1)

See:
  http://docs.scipy.org/doc/numpy/reference/routines.set.html

(Note that while in1d does the best it can, set operations on arrays
will usually be slower than if you used a more appropriate data type
like 'set' or 'dict'.)

-n

-- 
Nathaniel J. Smith
Postdoctoral researcher - Informatics - University of Edinburgh
http://vorpus.org