PYTHON

python test if value is np.nan

import numpy as np

mynan = np.nan
mynum = 18

print("NaN? : ", np.isnan(mynan)) # Use np.isnan() to test
print("NaN? : ", np.isnan(mynum))

# Results:
# Nan? : True
# NaN? : False

check nan values in a np array

array_has_nan = np.isnan(array_sum)

python check if nan

import math
x = float('nan')
math.isnan(x)
True

python test is nan

math.isnan(n)

check if a value is nan pandas

import numpy as np
import pandas as pd

val = np.nan

print(pd.isnull(val))
# True

check if value is NaN

Number.isNaN(123)

check if something is nan python

import math
print math.isnan(float('NaN'))OutputTrue
print math.isnan(1.0)OutputFalse

Check np.nan value

import pandas as pd
import numpy as np

df = pd.DataFrame(
	[[np.nan, 72, 67],
	[23, 78, 62],
	[32, 74, np.nan],
	[np.nan, 54, 76]],
	columns=['a', 'b', 'c'])

value = df.at[0, 'a']  #nan
isNaN = np.isnan(value)
print("Is value at df[0, 'a'] NaN :", isNaN)

value = df.at[0, 'b']  #72
isNaN = np.isnan(value)
print("Is value at df[0, 'b'] NaN :", isNaN)

how to check if a value is nan in python

# If you are doing any conditional operation and you want to check a if
# a single value is Null or not then you can use numpy's isna method.
np.isna(df[col][0])