# Invert Elements of Boolean Arrays In this article, we will learn how to invert the elements of a boolean array that contains boolean values like True or False.

## What is a Boolean Array in Python?

A boolean array is an array that has boolean values like True or False or maybe 1 or 0. A boolean array can be formed by using dtype = bool. Everything is considered true except for 0, None, False or empty strings.

```import numpy as np

arr_bool = np.array([1, 1.1, 0, None, 'a', '', True, False], dtype=bool)
print(arr_bool)
```

Output:

```[ True  True False False  True False  True False]
```

## Methods for inverting elements of Boolean Arrays

Following are the methods you can apply for inverting the elements of a boolean array in Python.

### Using the np.invert() function

Using the inbuilt np. invert() function you can invert the elements of a boolean array.

```import numpy as np
arr = np.array((True, True, False, True, False))
arr_inver = np.invert(arr)
print(arr_inver)
```

Output:

```[False False  True False  True]
```

### Using the if-else method

In this method, we will check the value of the index of each element in the array. If the value is zero it will be changed to 1 and vice-versa. Also if the value is True it will be changed to False.

```arr = ((0, 1, 0, 1))
a1 = list(arr)

for x in range(len(a1)):
if(a1[x]):
a1[x] = 0
else:
a1[x] = 1

print(a1)
```

Output:

```[1, 0, 1, 0]
```

## Conclusion

In summary, we learned different ways to invert the elements of a boolean array in python. Numpy is a flexible python library and provides a variety of functions to work with.