matrix to coordinates
The two functions row(), col() are useful here: aa <- data.frame(r=as.vector(row(m)), c=as.vector(col(m)), v=as.vector(m)) There's no other ready-made function for this, AFAIK. - tom blackwell - u michigan medical school - ann arbor -
On Thu, 24 Apr 2003, juli g. pausas wrote:
Dear R-users,
I'm sure it must be a specific function or a better way to convert
matrix to x,y,z coordinates (and viceversa), than my function below (it
works). Any help?
m2coord <- function(m)
{
k <- nrow(m)*ncol(m)
aa <- data.frame(r=1:k, c=1:k, v=1:k)
k <- 0
for (i in 1:nrow(m))
for (j in 1:ncol(m))
{
k <- k+1
aa$f[k]=i; aa$c[k]=j; aa$v[k]=m[i,j]
}
aa
}
Juli
--
Juli G. Pausas
Centro de Estudios Ambientales del Mediterraneo (CEAM)
C/ C.R. Darwin 14, Parc Tecnologic,
46980 Paterna, Valencia, SPAIN
Tel: (+ 34) 96 131 8227; Fax: (+ 34) 96 131 8190
mailto:juli at ceam.es
http://www.gva.es/ceam