arrays - python: creating numpy nonzero index, value pair -

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i can index of non-zero numpy arrays follows:

a = np.array([0., 1., 0., 2.]) = np.nonzero(a)

this returns (array([1, 3]),). can corresponding values as:

v = a[i]

now create list each of (index, value) tuples. guess 1 way write for loop follows;

l = list() x in range(0, len(v)):     l.append((i[0][x], v[x]))

however, wondering if there better way without writing loop.

you use list comprehension

l = [(x, v[x]) x in i[0]]

or use zip other answers suggest


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