python实现矩阵乘法的方法
本文实例讲述了python实现矩阵乘法的方法。分享给大家供大家参考。具体实现方法如下：
defmatrixMul(A,B): res=[[0]*len(B[0])foriinrange(len(A))] foriinrange(len(A)): forjinrange(len(B[0])): forkinrange(len(B)): res[i][j]+=A[i][k]*B[k][j] returnres defmatrixMul2(A,B): return[[sum(a*bfora,binzip(a,b))forbinzip(*B)]forainA] a=[[1,2],[3,4],[5,6],[7,8]] b=[[1,2,3,4],[5,6,7,8]] printmatrixMul(a,b) printmatrixMul(b,a) print"-"*90 printmatrixMul2(a,b) printmatrixMul2(b,a) print"-"*90 fromnumpyimportdot printmap(list,dot(a,b)) printmap(list,dot(b,a)) #Out: #[[11,14,17,20],[23,30,37,44],[35,46,57,68],[47,62,77,92]] #[[50,60],[114,140]] #------------------------------------------------------------------------ #[[11,14,17,20],[23,30,37,44],[35,46,57,68],[47,62,77,92]] #[[50,60],[114,140]] #------------------------------------------------------------------------ #[[11,14,17,20],[23,30,37,44],[35,46,57,68],[47,62,77,92]] #[[50,60],[114,140]]
希望本文所述对大家的Python程序设计有所帮助。