numpy operator to compare two vectors

Question

I am wondering if there is a python-numpy operator to compare two vectors of the same shape. Specifically,

Can I get the results directly through a numpy API and what is it? Thanks very much!

Bruno Mello · Accepted Answer · 2020-04-01 17:47:56Z

2

If your arrays are a and b:

c = ((np.repeat(a, b.shape[0]).reshape(a.shape[0], b.shape[0]) - b) == 0).astype(int)

or, as hpaulj and FBruzzesi said:

c = (a[:, None] == b).astype(int)

answered Apr 1, 2020 at 17:07

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4 Comments

simpler: a[:,None]==b

@hpaulj That was genius!

Just as a final remark, consider converting to integer: (a[:, None] == b).astype(int) to have zeros and ones instead of boolean values.

@BrunoMello It did work. That was amazing with simplicity. Thank you all for your kind and prompt reply.