NumPy amax()

Summary: in this tutorial, you will learn how to use the numpy amax() function to find the maximum element in an array.

Introduction to the NumPy amax() function #

The amax() function returns the maximum element of an array or maximum element along an axis. The following shows the syntax of the amax() function:

numpy.amax(a, axis=None, out=None, keepdims=<no value>, initial=<no value>, where=<no value>)Copy

The amax() function is equivalent to the max() method of the ndarray object:

ndarray.max(axis=None, out=None, keepdims=False, initial=<no value>, where=True)Copy

NumPy amax() function examples #

Let’s take some examples of using the amax() function.

1) Using numpy amax() function on 1-D array example #

The following example uses the numpy amax() function to find the maximum value in a 1-D array:

import numpy as np


a = np.array([1, 2, 3])
min = np.amax(a)
print(max)Copy

Output:

1Copy

How it works.

First, create a new array that has three numbers 1, 2, and 3:

a = np.array([1, 2, 3])Copy

Second, find the maximum number using the amax() function:

max = np.amax(a)Copy

Third, display the result:

print(max)Copy

2) Using numpy amax() function on multidimensional array examples #

The following example uses the amax() funciton to find the maximum number in a 2-D array:

import numpy as np

a = np.array([
    [1, 2],
    [3, 4]]
)
max = np.amax(a)
print(max)Copy

Output:

1Copy

If you want to find the maximum value on each axis, you can use the axis argument. For example, the following uses the amax() function to find the maximum value on axis 0:

import numpy as np

a = np.array([
    [1, 2],
    [3, 4]]
)
max = np.amax(a, axis=0)
print(max)Copy

Output:

[3 4]Copy

Similarly, you can use the amax() function to find the maximum value on axis 1:

import numpy as np

a = np.array([
    [1, 2],
    [3, 4]]
)
max = np.amax(a, axis=1)
print(max)Copy

Output:

[2 4]Copy

Summary #

• Use the numpy amax() function to find the maximum element in an array or maximum element along an axis.