# To find the Maximum and Minimum value in a NumPy Array

In this tutorial, we’ll learn about NumPy library, NumPy array and how to calculate the maximum and minimum value in NumPy array.

`np.amax(array)`

`np.amin(array)`

These two functions can be used to achieve our target here.

## The maximum and minimum value in NumPy Array

import numpy as np # 1D array arr = np.arange(10) print("arr : ", arr) print("Maximum of arr : ", np.amax(arr)) print("Minimum of arr : ", np.amin(arr)) # 2D array arr = np.arange(10).reshape(2, 5) print("\narr : ", arr) # Maximum and minimum of the flattened array print("\nMax of arr, axis = None : ", np.amax(arr)) print("\nMin of arr, axis = None : ", np.amin(arr)) # Maxima and minima along the first axis # axis 0 means vertical print("Max of arr, axis = 0 : ", np.amax(arr, axis = 0)) print("Min of arr, axis = 0 : ", np.amin(arr, axis = 0)) # Maxima and minima along the second axis # axis 1 means horizontal print("Max of arr, axis = 1 : ", np.amax(arr, axis = 1)) print("Min of arr, axis = 1 : ", np.amin(arr, axis = 1))

Output:

arr : [0 1 2 3 4 5 6 7 8 9] Max of arr : 9 Min of arr : 0 arr : [[0 1 2 3 4] [5 6 7 8 9]] Max of arr, axis = None : 9 Min of arr, axis = None : 0 Max of arr, axis = 0 : [5 6 7 8 9] Min of arr, axis = 0 : [0 1 2 3 4] Max of arr, axis = 1 : [4 9] Min of arr, axis = 1 : [0 5]

In the code above we have used 2 new functions:

**Numpy.amax()**

It is used to calculate the value of the maximum in an array. However, if the axis is mentioned it will find the maximum value along the mentioned axis.

**Syntax of NumPy.amax() :**

numpy.amax(arr, axis = None, out = None, keepdims = <class numpy._globals._NoValue>)

**Numpy.amin()**

It is used to calculate the value of the minimum in an array. Although if the axis is mentioned it will find the minimum value along the mentioned axis.

**Syntax of NumPy.amin() :**

numpy.amin(arr, axis = None, out = None, keepdims = <class numpy._globals._NoValue>)

**Parameters:**

- Arr: It is the input data in the form of an array.
- Axis: It specifies the axis along which we want to calculate the maximum value.
- Out: It is an array in which the result will be stored. It is optional.
- Keepdims: If set to true, the axes which are reduced will be left in the result as dimensions size 1.

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