sciPy stats.nanmedian() function | Python

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scipy.stats.nanmedian(array, axis=0) function calculates the median by ignoring the Nan (not a number) values of the array elements along the specified axis of the array.

Parameters :
array : Input array or object having the elements, including Nan values, to calculate the median.
axis : Axis along which the median is to be computed. By default axis = 0

Returns : median of the array elements (ignoring the Nan values) based on the set parameters.

Code #1:

# median  
import scipy 
import numpy as np 
  
arr1 = [1, 3, np.nan, 27, 2, 5]  
   
print("median using nanmedian :", scipy.nanmedian(arr1)) 
  
print("median without handling nan value :", scipy.median(arr1))  

Output:

median using nanmedian : 3.0
median without handling nan value : nan

Code #2: With multi-dimensional data

# median  
from scipy import median 
from scipy import nanmedian 
import numpy as np 
  
arr1 = [[1, 3, 27],  
        [3, np.nan, 6],  
        [np.nan, 6, 3],  
        [3, 6, np.nan]]  
   
print("median is :", median(arr1))  
print("median handling nan :", nanmedian(arr1))  
  
# using axis = 0 
print("\nmedian is with default axis = 0 : \n",  
      median(arr1, axis = 0)) 
print("\nmedian handling nan with default axis = 0 : \n",  
      nanmedian(arr1, axis = 0)) 
  
# using axis = 1 
print("\nmedian is with default axis = 1 : \n",  
      median(arr1, axis = 1))   
print("\nmedian handling nan with default axis = 1 : \n",  
      nanmedian(arr1, axis = 1))   

Output:

median is : nan
median handling nan : 3.0

median is with default axis = 0 : 
 [ nan  nan  nan]

median handling nan with default axis = 0 : 
 [ 3.  6.  6.]

median is with default axis = 1 : 
 [  3.  nan  nan  nan]

median handling nan with default axis = 1 : 
 [ 3.   4.5  4.5  4.5]