# Check if NumPy Array contains only empty strings – Python

This tutorial will discuss about unique ways to check if numpy array contains only empty strings.

## Method 1: using numpy.char.str_len()

The `numpy` module in Python provides a function `numpy.char.str_len()`. It accepts a string array as an argument, and returns an array of integers. In the returned array, a value at the `ith` index represents the size of string at the `ith` index in passed string array.

So, to check if a Numpy Array contains only empty strings, we can pass the NumPy array to method `numpy.char.str_len()`, and compare the returned array with zero. It will give a Boolean Array. In this array, each True value represents that the corresponding value in the original NumPy array is an empty string.

Then we can use the `numpy.all()` method to check if boolean array has only True values or not. If it returns True, then it means original numpy array has empty strings only.

Let’s see the complete example,

```import numpy as np

# Create a NumPy Array
arr = np.array(['', '', ''])

# check if numpy array has empty strings
if np.all(np.char.str_len(arr) == 0):
print("The NumPy Array contains only empty strings")
else:
print("The NumPy Array does not contain only empty strings")
```

Output

```The NumPy Array contains only empty strings

```

## Method 2: using all() method

Iterate over all strings of NumPy Array, and for each string check if its size is 0 or not. Do, all this in a generator expression, and it will give a boolean list. In this list, each True value represents that the corresponding value in the original numpy array is an empty string.

Then we can use the `all()` method to check if boolean list has only True values or not. If it returns True, then it means original numpy array has empty strings only.

#### Latest Python - Video Tutorial

Let’s see the complete example,

```import numpy as np

# Create a NumPy Array
arr = np.array(['', '', ''])

# check if numpy array has empty strings
if all(len(x) == 0 for x in arr):
print("The NumPy Array contains only empty strings")
else:
print("The NumPy Array does not contain only empty strings")
```

Output

```The NumPy Array contains only empty strings

```

## Summary

We learned about two different ways to check if a NumPy array has only empty strings in Python. Thanks.

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