# Test array values for positive or negative infinity in Numpy

To test array for positive or negative infinity, use the numpy.isinf() method in Python Numpy. Returns a boolean array of the same shape as x, True where x == +/-inf, otherwise False.

NumPy uses the IEEE Standard for Binary Floating-Point for Arithmetic (IEEE 754). Errors result if the second argument is supplied when the first argument is a scalar, or if the first and second arguments have different shapes.

## Steps

At first, import the required library −

import numpy as np

Create an array with some inf values −

arr = np.array([1, 2, 10, 50, -np.inf, 0., np.inf])


Display the arrays −

print("Array...", arr)

Get the type of the arrays −

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


Get the dimensions of the Arrays −

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

Get the number of elements in the Array −

print("Number of elements...", arr.size)


To test array for positive or negative infinity, use the numpy.isinf() method in Python Numpy −

print("Test array for positive or negative infinity...",np.isinf(arr))

## Example

import numpy as np

# Create an array with some inf values
arr = np.array([1, 2, 10, 50, -np.inf, 0., np.inf])

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

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

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

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

# To test array for positive or negative infinity, use the numpy.isinf() method in Python Numpy
print("Test array for positive or negative infinity...",np.isinf(arr))

## Output

Array...
[ 1. 2. 10. 50. -inf 0. inf]

Our Array type...
float64

Our Array Dimensions...
1

Number of elements...
7

Test array for positive or negative infinity...
[False False False False True False True]