python中的求和矩阵列

I can sum the items in column zero fine. But where do I change the code to sum column 2, or 3, or 4 in the matrix? I'm easily stumped.

def main():
    matrix = []

    for i in range(2):
        s = input("Enter a 4-by-4 matrix row " + str(i) + ": ") 
        items = s.split() # Extracts items from the string
        list = [ eval(x) for x in items ] # Convert items to numbers   
        matrix.append(list)

    print("Sum of the elements in column 0 is", sumColumn(matrix))

def sumColumn(m):
    for column in range(len(m[0])):
        total = 0
        for row in range(len(m)):
            total += m[row][column]
        return total

main()

解决方案

您的代码更改为返回您指定的任何列的总和:

def sumColumn(m, column):
    total = 0
    for row in range(len(m)):
        total += m[row][column]
    return total

column = 1
print("Sum of the elements in column", column, "is", sumColumn(matrix, column))