Hi guys:
Sorry if this question is very basic. I’m learning basic matrix and
vectors multiplication to develop a population matrix model for
plants. I’m trying to multiply the elements of two vectors (each of
the “x” values by each of the “y” values) to obtain a square matrix of
xy values.
f.e.
x<-seq(5,205)
y<-seq(5,20,5)
stages<-c(“Sdl”, “Juv”, “Ad1”, “Ad2”)
If I just multiply xy as a matrix
xy<-matrix(x,y,nrow=4,ncol=4,dimnames=list(stages,stages))
I obtain this
xy
Sdl Juv A1 A2
Sdl 5 10 15 20
Juv 5 10 15 20
A1 5 10 15 20
A2 5 10 15 20
but what I want to obtain is this matrix
Sdl Juv A1 A2
Sdl 25 50 75 100
Juv 50 100 150 200
A1 75 50 225 300
A2 100 200 300 400
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