kdiag (a1,a2,…,an）=diog(ka1,ka2,…,kan) diag(a az,aliag(,bb) =diag(b:b2,..,b)diag(a,az: .…,an） =diag(ab:ab2,,a,b) (diag(a,a,,an》m=diaga,a,,a） 米 (aE)A=a(EA)=a(AE)=A(aE) 上页 ( ) ( ) n n kdiag a , a , , a diag ka , ka , , ka 1 2  = 1 2  ( ) ( ) ( ) ( ) ( ) n n n n n n diag a b a b a b diag b b b diag a a a diag a a a diag b b b , , , , , , , , , , , , , , , 1 1 2 2 1 2 1 2 1 2 1 2      = = * ( ) ( ) m n m m m n (diag a, a , , a ) diag a , a , , a 2  = 1 2  * (aE)A = a(EA) = a(AE) = A(aE)