Re: [R] row equality.

[James Bullard]

Sorry about that I realized that I posted code that doesnt work ... below

y should be replaced by the parameter m in the body of the function.

(I tried to clean it up to post, but that never works...)

has.row <- function(m, r) {
for (i in 1:length(m[,1])) {
  x <- ifelse(m[i,1:3] == r, 1, 0)

  if (sum(x) == 3) {
    return(TRUE)
  }
}
return(FALSE)
}

thanks. Jim

James Bullard wrote:

I think that this is an easy one...

I have a matrix where each row is an (x,y,z) triplet. Given a potential (xnew,ynew,znew) triplet I want to know if the matrix already contains a row with the new values (the space already has that point). I can do it using a for loop, but I would like to know if there is anyway in which I can do it without the for loop.

I do it now like this (this algorithm appears to be correct, but there are probably much cleaner ways to write it.)

has.row <- function(m, r) {
 for (i in 1:length(y[,1])) {
   x <- ifelse(y[i,1:3] == r, 1, 0)
   if (sum(x) == 3) {
     return(TRUE)
   }
 }
 return(FALSE)
}

Thanks, jim

______________________________________________
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html

--
James Bullard
[EMAIL PROTECTED]
760.267.0986

______________________________________________
R-help@stat.math.ethz.ch mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html