# Return the identity array and change the datatype of the output in Numpy

To return the identity array, use the numpy.identity() method in Python Numpy. The identity array is a square array with ones on the main diagonal. The 1s parameter is the number of rows (and columns) in n x n output. The "dtype" parameter is used to return the data-type of the output.

The function returns n x n array with its main diagonal set to one, and all other elements 0. The like parameter is a reference object to allow the creation of arrays which are not NumPy arrays. If an array-like passed in as like supports the __array_function__ protocol, the result will be defined by it. In this case, it ensures the creation of an array object compatible with that passed in via this argument.

## Steps

At first, import the required library −

import numpy as np

Create a 2d array. To return the identity array, use the numpy.identity() method in Python Numpy. The "dtype" parameter is used to return the data-type of the output −

arr = np.identity(4, dtype = int)


Display the array −

print("Array...", arr)

Get the type of the array −

print("Array type...", arr.dtype)


Get the shape of the array −

print("Array shape...", arr.shape)

Get the dimensions of the Array −

print("Array Dimensions...",arr.ndim)


Get the number of elements in the Array −

print("Array (count of elements)...",arr.size)

## Example

import numpy as np

# Create a 2d array
# To return the identity array, use the numpy.identity() method in Python Numpy
# The identity array is a square array with ones on the main diagonal.
# The 1s parameter is the number of rows (and columns) in n x n output
# The "dtype" parameter is used to return the ata-type of the output.
arr = np.identity(4, dtype = int)

# Display the array
print("Array...", arr)

# Get the type of the array
print("Array type...", arr.dtype)

# Get the shape of the array
print("Array shape...", arr.shape)

# Get the dimensions of the Array
print("Array Dimensions...",arr.ndim)

# Get the number of elements of the Array
print("Array (count of elements)...",arr.size)

## Output

Array...
[[1 0 0 0]
[0 1 0 0]
[0 0 1 0]
[0 0 0 1]]

Array type...
int64

Array shape...
(4, 4)

Array Dimensions...
2

Array (count of elements)...
16