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You can use the following methods to count the occurrences of elements in a NumPy array:

**Method 1: Count Occurrences of a Specific Value**

np.count_nonzero(x == 2)

**Method 2: Count Occurrences of Values that Meet One Condition**

np.count_nonzero(x 6)

**Method 3: Count Occurrences of Values that Meet One of Several Conditions**

np.count_nonzero((x == 2) | (x == 7))

The following examples show how to use each method in practice with the following NumPy array:

import numpy as np #create NumPy array x = np.array([2, 2, 2, 4, 5, 5, 5, 7, 8, 8, 10, 12])

**Example 1: Count Occurrences of a Specific Value**

The following code shows how to count the number of elements in the NumPy array that are equal to the value 2:

#count number of values in array equal to 2 np.count_nonzero(x == 2) 3

From the output we can see that **3** values in the NumPy array are equal to 2.

**Example 2: Count Occurrences of Values that Meet One Condition**

The following code shows how to count the number of elements in the NumPy array that have a value less than 6:

#count number of values in array that are less than 6 np.count_nonzero(x 6) 7

From the output we can see that **7** values in the NumPy array have a value less than 6.

**Example 3: Count Occurrences of Values that Meet One of Several Conditions**

The following code shows how to count the number of elements in the NumPy array that are equal to 2 or 7:

#count number of values in array that are equal to 2or7 np.count_nonzero((x == 2) | (x == 7)) 4

From the output we can see that **4** values in the NumPy array are equal to 2 or 7.

**Additional Resources**

The following tutorials explain how to perform other common operations in Python:

How to Calculate the Mode of NumPy Array

How to Map a Function Over a NumPy Array

How to Sort a NumPy Array by Column