I am new with Python, This is my code:
import numpy as np
x = [0, 0, 0, 0, 5, 0, 10, 5]
y = [4, 4, 4, 4, 9, 4, 2, 9]
def unitvector1 (x,y):
looplim=(len(x)+1)
for i in range (0,looplim):
z=i+1
alfa = np.arccos((x[i]*x[z])+(y[i]*y[z])) / ((np.sqrt(x[i] ^ 2+y[i] ^ 2) * np.sqrt(x[z] ^ 2+y[z] ^ 2)))
beta =+ (180-alfa)
return (beta)
temp=unitvector1(x,y)
print(temp)
And I am getting this error:
IndexError: list index out of range
I tried to do it with two for loops but it did not work.
Your help is much needed, Many thanks in advance for your help.
4 Answers
Lists are indexed starting from 0, so for a list of length, say, 13, the last valid index is 12, i.e., 1 less than the length.
When you do looplim=(len(x)+1) and then for i in range (0,looplim), the last value of i is looplim-1 which is equal to len(x), so it's the length rather than 1 less than that.
looplim=len(x)
for i in range(looplim-1):
alfa = np.arccos((x[i]*x[z])+(y[i]*y[z])) / ((np.sqrt(x[i] ^ 2+y[i] ^ 2) *
np.sqrt(x[z] ^ 2+y[z] ^ 2)))
for each iteration value of "alfa" is nan
remove + 1 from looplim=(len(x)+1) and z = i+1 then run the code !
Okay, first u should look at your variable z. When i=7 z=8 and there are no eight’s index element in x array. Second, idk why you try “looplim”. If you want to do operations with n and n+1 elements in this way we can add next:
def unitvector1 (x,y):
for i in range (len(x)-1):
z=i+1
if z==len(x)+1:
z=0
alfa = np.arccos((x[i]*x[z])+(y[i]*y[z])) / ((np.sqrt(x[i] ^ 2+y[i] ^ 2) * np.sqrt(x[z] ^ 2+y[z] ^ 2)))
beta =+ (180-alfa)
return (beta)
But it’s not working! Because arccos(alpha) should have alpha<|1|
If you can explain what do you want to count, maybe we can help you
