IndexError：索引10超出了大小为10的轴0的范围

Question

我在数值上为x网格和x向量以及时间网格设置了网格，但我还是为x（位置）设置了一个数组，该数组只能在0到20之间，并且t（时间）从0到因此，为了求解热方程，请先将其设为1000。但是每次例如要执行步骤10时，都会出现错误：

"Traceback (most recent call last):
File "/home/universe/Desktop/Python/Heat_1.py", line 33, in <module>
x[i] = a + i*h
IndexError: index 10 is out of bounds for axis 0 with size 10"

这是我的代码：

from math import sin,pi
import numpy
import numpy as np

#Constant variables
N = int(input("Number of intervals in x (<=20):"))
M = int(input("Number of time steps (<=1000):" ))

#Some initialised varibles
a = 0.0
b = 1.0
t_min = 0.0
t_max = 0.5

# Array Variables
x = np.linspace(a,b, M)
t = np.linspace(t_min, t_max, M) 


#Some scalar variables
n = []                         # the number of x-steps
i, s = [], []                  # The position and time

# Get the number of x-steps to use
for n in range(0,N):
    if n > 0 or n <= N:
         continue

# Get the number of time steps to use
for m in range(0,M):
    if m > 0 or n <= M:
         continue

# Set up x-grid  and x-vector
h =(b-a)/n
for i in range(0,N+1):
    x[i] = a + i*h

# Set up time-grid
k = (t_max - t_min)/m
for s in range(0, M+1):
    t[s] = t_min + k*s

print(x,t)

Answer 1

您尝试索引超出范围：

for s in range(0, M+1):
    t[s] = t_min + k*s

改成：

for s in range(M):
    t[s] = t_min + k*s

而且有效。

您创建t的长度为M：

t = np.linspace(t_min, t_max, M) 

因此，您只能访问中的M元素t。

Python总是从零开始索引。因此：

for s in range(M):

将执行M循环，而：

for s in range(0, M+1):

会做M+1循环。