read a matrix to find a value
Judit -
Does this example provide any insight?
pop <- matrix(0,7,7)# Population matrix when t==0 pop[sample(1:length(pop),1)] <-1 #Population matrix when t==1 which(pop!=0,arr.ind=TRUE)
row col [1,] 3 4 - Phil Spector Statistical Computing Facility Department of Statistics UC Berkeley spector at stat.berkeley.edu
On Wed, 1 Dec 2010, Barroso, Judit wrote:
Dear all of you, I would like if someone can help me to know how I can read a matrix looking for positions in the matrix that are not null. I have a matrix with most of the "cells" or "positions" null, I am trying to know the invasion power of a plant (number 1 in the matrix when t==1). I would like to continue the model writing some condition when the value of the matrix in not null, but I don't know what function or loop I have to use to find the values > than 0 for the next step. pop <- matrix(0,7,7)# Population matrix when t==0 pop[sample(1:length(pop),1)] <-1 #Population matrix when t==1 Thanks a lot, Judit [[alternative HTML version deleted]]
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