举个小例子吧
A = 【4*3】
[ a11,a12,a13]
[ a21,a22,a23]
[ a31,a32,a33]
[ a41,a42,a43]
B =【3*2】
[ b11,b12]
[ b21,b22]
[ b31,b32]
C=A*B
=
[ a11*b11+a12*b21+a13*b31,a11*b12+a12*b22+a13*b32]
[ a21*b11+a22*b21+a23*b31,a21*b12+a22*b22+a23*b32]
[ a31*b11+a32*b21+a33*b31,a31*b12+a32*b22+a33*b32]
[ a41*b11+a42*b21+a43*b31,a41*b12+a42*b22+a43*b32]
