迭代列表以获取指定序列中的值

Question

I had an initial tuple, over which I was trying to iterate to perform further calculations. However, I end up having an error " too many values to unpack " which was solved by following suggestions from this question asked previously( Python - too many values to unpack ). However, right now after converting it to a list, I have another error 'list' object has no attribute 'reshape' .

My code looks like this:

Z=[([A,3],[A1,6])]  #A and A1 are 2x2 matrices 
y=[]
for data,label in Z:

    x = data.reshape((4,))
    y.append(int(label))

I can understand the cause of the error. In this case, I want the loop to run two times (because I have two sets of data [A-3,A1-6]) and data, label to be: A , 3 and A1 , 6 . But it is being misread as data = [A,3] and label = [A1,6] .

What would be the proper way to loop through this list and generate data the way I want?

NB: The Z doesn't need to be a list, I can change it to a tuple if that makes life easier.

Answer 1

The tuple is inside a list. You're just iterating over the list, but not over the tuple elements. You need nested loops.

for t in Z:
    for data, label in t:
        x = data.reshape(4,)
        y.append(int(label))

You don't need the nested loops if you get rid of the list.

Z=([A,3],[A1,6])  #A and A1 are 2x2 matrices 
y=[]
for data,label in Z:
    x = data.reshape((4,))
    y.append(int(label))