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You can use the following basic syntax to find the mode of a NumPy array:

**#find unique values in array along with their counts
vals, counts = np.unique(array_name, return_counts=True)
#find mode
mode_value = np.argwhere(counts == np.max(counts))**

Recall that the **mode** is the value that occurs most often in an array.

Note that itâ€™s possible for an array to have one mode or multiple modes.

The following examples show how to use this syntax in practice.

**Example 1: Calculating Mode of NumPy Array with Only One Mode**

The following code shows how to find the mode of a NumPy array in which there is only one mode:

import numpy as np #create NumPy array of values with only one mode x = np.array([2, 2, 2, 3, 4, 4, 5, 5, 5, 5, 7]) #find unique values in array along with their counts vals, counts = np.unique(x, return_counts=True) #find mode mode_value = np.argwhere(counts == np.max(counts)) #print list of modes print(vals[mode_value].flatten().tolist()) [5] #find how often mode occurs print(np.max(counts)) 4

From the output we can see that the mode is **5** and it occurs **4** times in the NumPy array.

**Example 2: Calculating Mode of NumPy Array with Multiple Modes**

The following code shows how to find the mode of a NumPy array in which there are multiple modes:

import numpy as np #create NumPy array of values with multiple modes x = np.array([2, 2, 2, 3, 4, 4, 4, 5, 5, 5, 7]) #find unique values in array along with their counts vals, counts = np.unique(x, return_counts=True) #find mode mode_value = np.argwhere(counts == np.max(counts)) #print list of modes print(vals[mode_value].flatten().tolist()) [2, 4, 5] #find how often mode occurs print(np.max(counts)) 3

From the output we can see that this NumPy array has three modes: **2**, **4**, and **5**.

We can also see that each of these values occurs **3** times in the array.

**Additional Resources**

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

How to Map a Function Over a NumPy Array

How to Find Index of Value in NumPy Array

How to Calculate the Magnitude of a Vector Using NumPy