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

np where nan

np.argwhere(np.isnan(x))

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)