numpy "insert" 不插入任何东西

Question

我在使用 Numpy python 库向数组插入日期时遇到问题。这是我遇到问题的代码：

import numpy as np
arr = np.array([]) # here is the array 
UserInput = int(input("type the lenght of the array")) # the user decide the lenght of the array
arr.resize(UserInput) 
#now if we print the array it will be [0,0,0,0,0,0...]
def inserting(): # simple function that let the user choose which index he/she want to change
...
  TheUserChoose = int(input("choose the index that you want to change its value")) # now let's assume the user choose the index number '1'
  theNewValue = int(input("type here")) # we type '7' okay
  np.insert(arr,TheUserChoose ,theNewValue )
  print(arr)
  >>> [0,0,0,0,...0] Nothing change 
  # Also if I type the index and the value manually like "np.insert(arr,1 ,7)" nothing happened

我最近才开始python，所以我是初学者，但我有基础。

Answer 1

NumPy 的数组是不可变的（在大多数情况下），因此 np.insert 不会这样做 in-place，而是 returns 一个新数组，因此您需要：

    arr = np.insert(arr,TheUserChoose ,theNewValue ) #note the arr =

numpy "insert" 不插入任何东西

numpy "insert" does not insert anything

python

arrays

numpy

python-3.x