a<-c(1,1,1)
A<-a
A<-matrix(a,3,1)

b<-c(-0.01,-0.015,-0.003,-0.003,-0.01,-0.015,-0.015,-0.003,-0.01)
B<-matrix(b,3,3,byrow=TRUE)


B*B
B%*%B

n<-c(1,2,3,4)
diag(n)