import math
 
 
x = math.nan
print(f"x contains {x}")
 
# checks if variable is equal to NaN
if(math.isnan(x)):
    print("x == nan")
else:
    print("x != nan")

x contains nan
x == nan

import math
 
 
def isNan(number):
     
    # This function compares number to itself.
    # NaN != NaN and therefore it will return
    # true if the number is Nan
    return number != number
 
# Driver Code 
x = math.nan
print(isNan(x))

True

import math
 
# Function checks if negative or
# positive infinite.
def check(x):
   
    if(math.isinf(x) and x > 0):
        print("x is Positive inf")
     
    elif(math.isinf(x) and x < 0):
        print("x is negative inf")
     
    else:
        print("x is not inf")
 
 
# Creating inf using math module.
number = math.inf
check(number)
 
number = -math.inf
check(number)

x is Positive inf
x is negative inf

# pip install numpy
import numpy as np
 
print(np.isneginf([np.inf, 0, -np.inf]))
print(np.isposinf([np.inf, 0, -np.inf]))

[False False  True]
[ True False False]