Question

我想用矩阵存储所有For Loop值（），

但我不知道该怎么做。

感谢您的评论〜

import numpy as np

T1 = 3
T3 = 10

ydd = 0;
wdd = 0;
tt = 0;

t=0
for t in np.arange (t,T3,0.001) :  
    if t <= T1:
        yd = 1/2*amax*(t**2)  
        wd = amax*t    
        ad = amax
    elif t > T1:
        yd = amax*(t**6)  
        wd = amax*t    
        ad = amax

Answer 1

import numpy as np

T1 = 3
T3 = 10

ydd = 0;
wdd = 0;
tt = 0;

## declare arrays to store the data
## size of arrays is bit tricky. 
## I am just calculating the number of times you are going to run the for loop. 
## The array has to be same size
t=0
i=0 

yd = np.zeros( int((T3-t)*1.0/0.001) )
wd = np.zeros( int((T3-t)*1.0/0.001) )
ad = np.zeros( int((T3-t)*1.0/0.001) )    
for t in np.arange (t,T3,0.001) :  
    if t <= T1:
        yd[i] = 1/2*amax*(t**2)  
        wd[i] = amax*t    
        ad[i] = amax
    elif t > T1:
        yd[i] = amax*(t**6)  
        wd[i] = amax*t    
        ad[i] = amax
    i = i+1
    ## store in the array instead of variable

您现在可以访问yd，wd和ad数组中的所有值免责声明：在不运行代码的情况下发布，因为我不确定amax是什么。

Answer 2

没有for循环这样做。它的速度要快得多（尤其是 numpy！），并且对于没有相互依赖性的计算更自然/可读。

vals = np.arange(t, T3, 0.001)
cond = vals <= T1

yd = np.zeros_like(vals)
yd[cond] = (0.5 * amax * vals**2)[cond]
yd[!cond] = (amax * vals**6)[!cond]

wd = amax * vals
ad = np.full_like(vals, amax)

如何用矩阵获取循环外的循环值？

2 个答案: