Question

我想在我的程序中做嵌套循环。但是，此代码不符合我的期望。

X=[0,1,1,1,0]

length=len(X)
for i,val in enumerate(X):
    a=0
    count=0
    while (count<length):
        a=15+a
        print (a)
        HWPQ=np.matrix([[1, 0, 0, 0], [0, math.cos(4*math.radians(a)), 
        math.sin(4*math.radians(a)), 0], [0, math.sin(4 * math.radians(a)), - 
        math.cos(4 * math.radians(a)), 0], [0, 0, 0, -1]])
        result=HWPQ*val
        print (result)
        count=count +1
    print ("\n")

应该在此程序中，我想使用循环为每个元素更新a的值。例如：

X=0 for a=0
X=1 for a=15
X=1 for a=30
X=1 for a=45
X=0 for a=60

结果应该是我手动计算的结果：

[[ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]]
[[ 1.         0.         0.         0.       ]
 [ 0.         0.5        0.8660254  0.       ]
 [ 0.         0.8660254 -0.5        0.       ]
 [ 0.         0.         0.        -1.       ]]
[[ 1.         0.         0.         0.       ]
 [ 0.        -0.5        0.8660254  0.       ]
 [ 0.         0.8660254  0.5        0.       ]
 [ 0.         0.         0.        -1.       ]]
[[  1.00000000e+00   0.00000000e+00   0.00000000e+00   0.00000000e+00]
 [  0.00000000e+00  -1.00000000e+00   1.22464680e-16   0.00000000e+00]
 [  0.00000000e+00   1.22464680e-16   1.00000000e+00   0.00000000e+00]
 [  0.00000000e+00   0.00000000e+00   0.00000000e+00  -1.00000000e+00]]
 [[ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]]

Answer 1

您的代码中似乎有很多不必要的变量，例如count，X和i。删除它们并使用标准的for循环，您将得到：

X=[0,1,1,1,0]
a=0
for val in X:
    print (a)
    HWPQ=np.matrix([
        [1, 0, 0, 0], 
        [0, math.cos(4*math.radians(a)), math.sin(4*math.radians(a)), 0], 
        [0, math.sin(4 * math.radians(a)), - math.cos(4 * math.radians(a)), 0],
        [0, 0, 0, -1]])
    result=HWPQ*val
    print (result)
    a=15+a
    print ("\n")

这将创建所需的输出。

0
[[ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]]


15
[[ 1.         0.         0.         0.       ]
 [ 0.         0.5        0.8660254  0.       ]
 [ 0.         0.8660254 -0.5        0.       ]
 [ 0.         0.         0.        -1.       ]]


30
[[ 1.         0.         0.         0.       ]
 [ 0.        -0.5        0.8660254  0.       ]
 [ 0.         0.8660254  0.5        0.       ]
 [ 0.         0.         0.        -1.       ]]


45
[[  1.00000000e+00   0.00000000e+00   0.00000000e+00   0.00000000e+00]
 [  0.00000000e+00  -1.00000000e+00   1.22464680e-16   0.00000000e+00]
 [  0.00000000e+00   1.22464680e-16   1.00000000e+00   0.00000000e+00]
 [  0.00000000e+00   0.00000000e+00   0.00000000e+00  -1.00000000e+00]]


60
[[ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]
 [ 0.  0.  0.  0.]]

如何在python中执行嵌套循环

1 个答案: