Numpy maskearray .至少 _3d()函数| Python
原文:https://www . geesforgeks . org/numpy-masked array-至少 _3d-function-python/
numpy.MaskedArray.atleast_3d()
函数用于将输入转换为至少三维的屏蔽数组。标量、一维和二维数组被转换为三维数组,而高维输入被保留。
语法:
numpy.ma.atleast_3d(*arys)
参数: arys:【array _ like】一个或多个输入数组。
返回:一个数组或数组列表,每个数组都有
arr.ndim >= 3
代码#1 :
# Python program explaining
# numpy.MaskedArray.atleast_3d() method
# importing numpy as geek
# and numpy.ma module as ma
import numpy as geek
import numpy.ma as ma
# creating input arrays
in_arr1 = geek.array([ 3, -1, 5, -3])
print ("1st Input array : ", in_arr1)
in_arr2 = geek.array(2)
print ("2nd Input array : ", in_arr2)
in_arr3 = geek.array([[1, 2], [ 3, -1], [ 5, -3]])
print ("3rd Input array : ", in_arr3)
# Now we are creating masked array.
# by making entry as invalid.
mask_arr1 = ma.masked_array(in_arr1, mask =[ 1, 0, 1, 0])
print ("1st Masked array : ", mask_arr1)
mask_arr2 = ma.masked_array(in_arr2, mask = 0)
print ("2nd Masked array : ", mask_arr2)
mask_arr3 = ma.masked_array(in_arr3, mask =[[ 1, 0], [ 0, 1], [ 0, 0]])
print ("3rd Masked array : ", mask_arr3)
# applying MaskedArray.atleast_3d methods
# to masked array
out_arr = ma.atleast_2d(mask_arr1, mask_arr2, mask_arr3)
print ("Output masked array : ", out_arr)
Output:
1st Input array : [ 3 -1 5 -3]
2nd Input array : 2
3rd Input array : [[ 1 2]
[ 3 -1]
[ 5 -3]]
1st Masked array : [-- -1 -- -3]
2nd Masked array : 2
3rd Masked array : [[-- 2]
[3 --]
[5 -3]]
Output masked array : [masked_array(data=[[--, -1, --, -3]],
mask=[[ True, False, True, False]],
fill_value=999999), masked_array(data=[[2]],
mask=[[False]],
fill_value=999999), masked_array(
data=[[--, 2],
[3, --],
[5, -3]],
mask=[[ True, False],
[False, True],
[False, False]],
fill_value=999999)]
代码#2 :
# Python program explaining
# numpy.MaskedArray.atleast_3d() method
# importing numpy as geek
# and numpy.ma module as ma
import numpy as geek
import numpy.ma as ma
# creating input array
in_arr = geek.array([[[ 2e8, 3e-5]], [[ -45.0, 2e5]]])
print ("Input array : ", in_arr)
# Now we are creating a masked array.
# by making one entry as invalid.
mask_arr = ma.masked_array(in_arr, mask =[[[ 1, 0]], [[ 0, 0]]])
print ("3D Masked array : ", mask_arr)
# applying MaskedArray.atleast_3d methods
# to masked array
out_arr = ma.atleast_3d(mask_arr)
print ("Output 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]]]