Python numpy.insert()用法及代碼示例

關於：
numpy.insert(數組，對象，值，軸=無)：沿提到的軸在給定索引之前插入值。
參數：

array   : [array_like]Input array. 
object  : [int, array of ints]Sub-array with the index or indices before 
     which values is inserted
values  : [array_like]values to be added in the arr. Values should be 
     shaped so that arr[...,obj,...] = values. If the type of values is different from 
     that of arr, values is converted to the type of arr
axis    : Axis along which we want to insert the values. By default, it 
     object is applied to flattened array

返回：

An copy of array with values being inserted as per the mentioned object along a given axis.

代碼1：從一維數組中刪除

# Python Program illustrating 
# numpy.insert() 
  
import numpy as geek 
  
#Working on 1D 
arr = geek.arange(5) 
print("1D arr : \n", arr) 
print("Shape : ", arr.shape) 
  
# value = 9 
# index = 1    
# Insertion before first index 
a = geek.insert(arr, 1, 9) 
print("\nArray after insertion : ", a) 
print("Shape : ", a.shape) 
  
  
# Working on 2D array  
arr = geek.arange(12).reshape(3, 4) 
print("\n\n2D arr : \n", arr) 
print("Shape : ", arr.shape) 
  
a = geek.insert(arr, 1, 9, axis = 1) 
print("\nArray after insertion : \n", a) 
print("Shape : ", a.shape)

輸出：

1D arr : 
 [0 1 2 3 4]
Shape :  (5,)

Array after insertion :  [0 9 1 2 3 4]
Shape :  (6,)


2D arr : 
 [[ 0  1  2  3]
 [ 4  5  6  7]
 [ 8  9 10 11]]
Shape :  (3, 4)

Array after insertion : 
 [[ 0  9  1  2  3]
 [ 4  9  5  6  7]
 [ 8  9  9 10 11]]
Shape :  (3, 5)

代碼2：使用標量

# Python Program illustrating 
# numpy.insert() 
  
import numpy as geek 
  
# Working on 2D array  
arr = geek.arange(12).reshape(3, 4) 
print("2D arr : \n", arr) 
print("Shape : ", arr.shape) 
  
# Working with Scalars 
a = geek.insert(arr, [1], [[6],[9],], axis = 0) 
print("\nArray after insertion : \n", a) 
print("Shape : ", a.shape) 
  
# Working with Scalars 
a = geek.insert(arr, [1], [[8],[7],[9]], axis = 1) 
print("\nArray after insertion : \n", a) 
print("Shape : ", a.shape)

輸出：

2D arr : 
 [[ 0  1  2  3]
 [ 4  5  6  7]
 [ 8  9 10 11]]
Shape :  (3, 4)

Array after insertion : 
 [[ 0  1  2  3]
 [ 6  6  6  6]
 [ 9  9  9  9]
 [ 4  5  6  7]
 [ 8  9 10 11]]
Shape :  (5, 4)

Array after insertion : 
 [[ 0  8  1  2  3]
 [ 4  7  5  6  7]
 [ 8  9  9 10 11]]
Shape :  (3, 5)

代碼3：在不同點插入

# Python Program illustrating 
# numpy.insert() 
  
import numpy as geek 
  
#Working on 1D 
arr = geek.arange(6).reshape(2, 3) 
print("1D arr : \n", arr) 
print("Shape : ", arr.shape) 
  
# value = 9 
# index = 1    
# Insertion before first index 
a = geek.insert(arr, (2, 4), 9) 
print("\nInsertion at two points : ", a) 
print("Shape : ", a.shape) 
  
  
# Working on 2D array  
arr = geek.arange(12).reshape(3, 4) 
print("\n\n2D arr : \n", arr) 
print("Shape : ", arr.shape) 
a = geek.insert(arr, (0, 3), 66, axis = 1) 
print("\nInsertion at two points : \n", a) 
print("Shape : ", a.shape)

輸出：

1D arr : 
 [[0 1 2]
 [3 4 5]]
Shape :  (2, 3)

Insertion at two points :  [0 1 9 2 3 9 4 5]
Shape :  (8,)


2D arr : 
 [[ 0  1  2  3]
 [ 4  5  6  7]
 [ 8  9 10 11]]
Shape :  (3, 4)

Insertion at two points : 
 [[66  0  1  2 66  3]
 [66  4  5  6 66  7]
 [66  8  9 10 66 11]]
Shape :  (3, 6)

參考文獻：
https://docs.scipy.org/doc/numpy/reference/generated/numpy.insert.html#numpy.insert

注意：
這些代碼無法在online-ID上運行。請在您的係統上運行它們以探索其工作原理。

相關用法

注：本文由純淨天空篩選整理自 numpy.insert() in Python。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。