为什么我总是得到错误 "list" object has no attribute 'tranpose'？

Question

这是我的代码：

class Matrix(object):
    """List of lists, where the lists are the rows of the matrix"""
    def __init__ (self, m=3,n=3,ma=[[1,2,3],[4,5,6], [7,8,9]]):
        self.n_rows=m
        self.n_cols=n
        self.matrix=ma=list(ma)          

    def __repr__(self):
        """String representation of a Matrix"""
        output= "Matrix: \n{} \n Your matrix has \n {} columns \n {} rows"\
                .format(self.matrix, self.n_cols, self.n_rows)
        return output

    def transpose (self):
        """Transpose the Matrix: Make rows into columns and columns into rows"""
        ma_transpose=[] 
        for r in zip(*self.matrix):
            ma_transpose.append(list(r)) 
        return ma_transpose


    def matrixmult (self,other):
        """Matrix Multiplication of 2 Matrices"""
        m2=other.matrix
        ma2_t=m2.transpose()
        table=[]
        for r in self.matrix:
            row=[]
            for n in ma2_t:
                row.append(dot_mult(r,n)) 
                table.append(row)   into a list of row
                res=table
        return res

但每次我尝试使用 matrixmult 函数时，我总是得到 "the list object has no attribute matrixmult"。这是为什么？我已经在前面的代码中定义了它 no?

ma2_t=m2.transpose()

AttributeError: 'list' 对象没有属性 'transpose'

有人帮忙吗？

Answer 1

matrixmult() 的最后一行是 returning a list。它应该 return 一个 Matrix 对象：

return Matrix(self.n_rows, other.n_cols, res)

同样在transpose方法中，你应该有：

return Matrix(self.n_cols, self.n_rows, ma_transpose)

为什么我总是得到错误 "list" object has no attribute 'tranpose'？

Why do I always get the error "list" object has no attribute 'tranpose'?

python

attributes

matrix