Numpy MaskedArray.argmax () Function | python

numpy.MaskedArray.argmax() returns an array of indices of the maximum values ​​along the given axis. Masked values ​​are treated as if they had fill_value.

Syntax: numpy.MaskedArray.argmax (axis = None, fill_value = None, out = None)

Parameters:
axis: [None, integer] If None, the index is into the flattened array, otherwise along the specified axis.
fill_value: [var, optional] Value used to fill in the masked values.
out: [ndarray , optional] A location into which the result is stored.
 – & gt; If provided, it must have a shape that the inputs broadcast to.
 – & gt; If not provided or None, a freshly-allocated array is returned.

Return: [index_array] A new integer_array is returned unless out is specified, in which case a reference to out is returned.

Code # 1:

# Python program explaining
# numpy.MaskedArray.argmax () method

 
# import numy as geek
# and numpy.ma module as ma

import numpy as geek

import numpy.ma as ma

 
# create input array

in_arr = geek.array ([ 1 , 2 , 3 , - 1 , 5 ])

print ( "Input array:" , in_arr)

 
# We are now creating a masked array.
# making the third entry invalid.

mask_arr = ma.masked_array (in_arr, mask = [ 0 , 0 < / code> , 1 , 0 , 0 ])

print ( "Masked array:" , mask_arr)

  
# applying MaskedArray.argmax methods to mask array

out_arr = mask_arr.argmax ( )

print ( "Index of max element in masked array: " , out_arr)

Output :

 Input array: [1 2 3 -1 5] Masked array: [1 2 - -1 5] Index of max element in masked array: 4 

Code No. 2:

# Python program explaining
# numpy.MaskedArray.argmax () method

 
# import numy as a geek
# and the numpy.ma module as ma

import numpy as geek

import numpy.ma as ma

 
# create input array

in_arr = geek.array ([ 10 , 20 , 30 , - 10 , 50 ])

print ( " Input array: " , in_arr)

  
# We now create a masked array
# invalidating the first third post.

mask_arr = ma.masked_array (in_arr, mask = [ 1 , 0 , 1 , 0 , 0 ])

print < / code> ( "Masked array:" , mask_arr)

 
# using MaskedArray.argmax methods to mask the array
# and filling the masked space by 100

out_arr = mask_arr.argmax (fill_value = 100 )

print ( "Index of max element in masked array: " , out_arr)

Output :

 Input array: [10 20 30 -10 50] Masked array: [- 20 - -10 50] Index of max element in masked array: 0