Hi All, I am wondering if there is an efficient way to do the following matrix multiplication, a[1,,] 1, 2 3, 4 a[2,,] 4, 3 2, 1 b[1,,] 5,6 7,8 b[2,,] 8,7 6,5 I need the result c, with c[1,,] = a[1,,] %*% b[1,,] c[2,,] = a[2,,] %*% b[2,,] Thanks in advance for any help.