Numpy MaskedArray.atleast_1d () Function | python



numpy.MaskedArray.atleast_1d() is used to transform input data into masked arrays with at least one dimension. numpy.MaskedArray.atleast_1d() the input is converted to one-dimensional arrays, while the larger input is preserved.

Syntax: numpy.ma.atleast_1d(*arys)

Parameters:
arys: [array_like] One or more input arrays.

Return: [ndarray] An array, or list of arrays, each with arr.ndim & gt; = 1

Code # 1:

# Python program explaining
# numpy.MaskedArray.atleast_1d () method

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

import numpy as geek 

import numpy.ma as ma 

 
# create input arrays

in_arr1 = geek.array ([[ 1 , 2 ], [ 3 , - 1 ], [ 5 , - 3 ]])

print ( " 1st Input array: " , in_arr1)

 

in_arr2 = geek.array ( 2 )

print ( "2nd Input array:" , in_arr2)

 
# We are now creating a masked array.
# invalidating the post.

mask_arr1 = ma.masked_array (in_arr1, mask = [[ 1 , 0 ], [ 0 , 1 ], [ 0 , 0 ]]) 

print ( " 1st Masked array: " , mask_arr1)

  

mask_arr2 = ma.masked_array (in_arr2, mask = 0

print ( "2nd Masked array:" , mask_arr2)

 
# applying MaskedArray.atleast_1d methods
# to the masked array

out_arr = ma.atleast_1d (mask_arr1, mask_arr2) 

print ( "Output masked array:" , out_arr) 

Output :

 1st Input array: [[1 2] [3 -1] [5 -3]] 2nd Input array: 2 1st Masked array: [[- 2] [3 -] [5 -3]] 2nd Masked array: 2 Output masked array: [masked_array (data = [[-, 2], [3, -], [ 5, -3]], mask = [[True, False], [False, True], [False, False]], fill_value = 999999), masked_array (data = [2], mask = [False], fill_value = 999999)] 

Code # 2:

# Python program explaining
# numpy.MaskedArray.atleast_1d () method

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

import numpy as g eek 

import numpy.ma as ma 

 
# create input array

in_arr = geek.array ([[[ 2e8 , 3e - 5 ]], [[ - 45.0 , 2e5 ]]])

print ( "Input array:" , in_arr)

 
# Now we create a masked array.
# making one entry invalid .

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

print ( "3D Masked array:" , mask_arr) 

 
# applying methods MaskedArray.atleast_1d
# into the masked array

out_arr = ma.atleast_1d (mask_arr) 

print ( " Ou tput masked array: " , out_arr)

Output:

 Input array: [[[2.0e + 08 3.0e-05]] [[-4.5e + 01 2.0e + 05]]] 3D Masked array : [[[- 3e-05]] [[-45.0 200000.0]]] Output masked array: [[[- 3e-05]] [[-45.0 200000.0]]]