Finding indexes of matching rows in two numpy arrays [duplicate]

Question

How can I find the indexes of the rows that match exactly between two numpy arrays. For example:

x = np.array(([0,1],
              [1,0],
              [0,0]))
y = np.array(([0,1],
              [1,1],
              [0,0]))

This should return:

matches = [0,2] # Match at row no 0 and 2

akuiper · Accepted Answer · 2017-09-14 01:54:48Z

5

np.flatnonzero((x == y).all(1))
# array([0, 2])

or:

np.nonzero((x == y).all(1))[0]

or:

np.where((x == y).all(1))[0]

answered Sep 14, 2017 at 1:54

akuiper

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Comments

Juan Albarracín · Accepted Answer · 2017-09-14 01:54:50Z

0

This works for every pair of numpy arrays if the length is the same:

matches = [i for i in range(len(x)) if x[i].tolist()==y[i].tolist()]

answered Sep 14, 2017 at 1:54

Juan Albarracín

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