You can use nonzero function. it returns the nonzero indices of the given input.
Easy Way
>>> (e > 15).nonzero()
(array([1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2]), array([6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9]))
to see the indices more cleaner, use transpose method:
>>> numpy.transpose((e>15).nonzero())
[[1 6]
[1 7]
[1 8]
[1 9]
[2 0]
...
Not Bad Way
>>> numpy.nonzero(e > 15)
(array([1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2]), array([6, 7, 8, 9, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9]))
or the clean way:
>>> numpy.transpose(numpy.nonzero(e > 15))
[[1 6]
[1 7]
[1 8]
[1 9]
[2 0]
...