Hello,
I am calculating this thing with vectors (b) and matrices (G,P):
b'G/sqrt(b'Pb)
where the denominator is a quadratic form and therefore always a scalar.
In Scilab, it is quite simple:
b'*G/sqrt(b'*P*b)
However, in R, the denominator is an (1x1)matrix and R claims it is non
conformable and I have to use drop() or as.numeric(). Like this:
b = 1:2
G=diag(1,2)
P=diag(2,2)
(t(b)%*%G) / drop( sqrt( t(b)%*%P%*%b ) )
[,1] [,2]
[1,] 0.3162278 0.6324555
So far, so good. My problem is solved. However I found a little bit annoying
that R is not so "clever" as to realize that b'Pb can be interpreted as a
scalar. I wonder :
would it be worth considering the implementation in R of
"recycling 1x1 matrix to scalars if appropriate"?
Just to leave the question on the ground...