Python numpy.append()
Python numpy.append()沿着上述axis在数组末尾追加值
语法 :
numpy.append(array, values, axis = None)
参数 :
array : [array_like]输入数组。
values : [array_like]要添加到arr中的值。值的形状应该是 arr[…,obj,…] = values。如果定义了轴,值可以是任何形状,因为它在使用前会被压扁。
axis :我们想沿着这个轴插入数值。默认情况下,数组是被压扁的。
返回 :
一个数组的副本,其值被附加在所述对象的最后。沿着一个给定的轴。
代码1:添加arrays
# Python Program illustrating
# numpy.append()
import numpy as geek
#Working on 1D
arr1 = geek.arange(5)
print("1D arr1 : ", arr1)
print("Shape : ", arr1.shape)
arr2 = geek.arange(8, 12)
print("\n1D arr2 : ", arr2)
print("Shape : ", arr2.shape)
# appending the arrays
arr3 = geek.append(arr1, arr2)
print("\nAppended arr3 : ", arr3)
输出 :
1D arr1 : [0 1 2 3 4]
Shape : (5,)
1D arr2 : [ 8 9 10 11]
Shape : (4,)
Appended arr3 : [ 0 1 2 3 4 8 9 10 11]
代码2:
# Python Program illustrating
# numpy.append()
import numpy as geek
#Working on 1D
arr1 = geek.arange(8).reshape(2, 4)
print("2D arr1 : \n", arr1)
print("Shape : ", arr1.shape)
arr2 = geek.arange(8, 16).reshape(2, 4)
print("\n2D arr2 : \n", arr2)
print("Shape : ", arr2.shape)
# appending the arrays
arr3 = geek.append(arr1, arr2)
print("\nAppended arr3 by flattened : ", arr3)
# appending the arrays with axis = 0
arr3 = geek.append(arr1, arr2, axis = 0)
print("\nAppended arr3 with axis 0 : \n", arr3)
# appending the arrays with axis = 1
arr3 = geek.append(arr1, arr2, axis = 1)
print("\nAppended arr3 with axis 1 : \n", arr3)
输出 :
2D arr1 :
[[0 1 2 3]
[4 5 6 7]]
Shape : (2, 4)
2D arr2 :
[[ 8 9 10 11]
[12 13 14 15]]
Shape : (2, 4)
Appended arr3 by flattened : [ 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15]
Appended arr3 with axis 0 :
[[ 0 1 2 3]
[ 4 5 6 7]
[ 8 9 10 11]
[12 13 14 15]]
Appended arr3 with axis 1 :
[[ 0 1 2 3 8 9 10 11]
[ 4 5 6 7 12 13 14 15]]