## Question

Asked By – gotgenes

NumPy has the efficient function/method `nonzero()`

to identify the indices of non-zero elements in an `ndarray`

object. What is the most efficient way to obtain the indices of the elements that *do* have a value of zero?

**Now we will see solution for issue: Find indices of elements equal to zero in a NumPy array **

## Answer

numpy.where() is my favorite.

```
>>> x = numpy.array([1,0,2,0,3,0,4,5,6,7,8])
>>> numpy.where(x == 0)[0]
array([1, 3, 5])
```

The method `where`

returns a tuple of ndarrays, each corresponding to a different dimension of the input. Since the input is one-dimensional, the `[0]`

unboxes the tuple’s only element.

This question is answered By – mtrw

**This answer is collected from stackoverflow and reviewed by FixPython community admins, is licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0 **