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Getting data out of a loop

4 messages · John Kane, jim holtman, Neuro LeSuperHéros

#
A stupid question but I just cannot see how to do
this.

I have a loop that does some calculations and puts the
results in a vector for each iteration, but I cannot
see how to get the data out of the loop in such a way
that I can use it.  I can print it but how do I get it
into a set of vectors or what ever.

Any help gratefully received.  Thanks

Example

cata <- c( 3,5,6,8,0, NA)
catb <- c( 1,2,3,4,5,6)
doga <- c(3,5,3,6,4, 0)
dogb <- c(2,4,6,8,10, 12)
rata <- c (NA, 5, 5, 4, 9, 0)
ratb <- c( 1,2,3,4,5,6)
bata <- c( 12, 42,NA, 45, 32, 54)
batb <- c( 13, 15, 17,19,21,23)
id <- Cs(a,b,b,c,a,b)
site <- c(1,1,4,4,1,4)
mat1 <-  cbind(cata, catb, doga, dogb, rata, ratb,
bata, batb)
Df <- data.frame(site, id, mat1)
nn <- levels(Df$id)

Df
nn
rate <- c(2,3,4)

for (i in 1: length(nn)) {
dd<- subset(Df, id==nn[i])   
scat <- sum(c(dd$cata,dd$catb), na.rm=T)
sdog <- sum(c(dd$doga,dd$dogb), na.rm=T) 
srat <- sum(c(dd$rata, dd$ratb), na.rm=T)
sbat <- sum(c(dd$bata,dd$batb), na.rm=T)
sss <- c(scat,sdog, srat,sbat) * rate[i]
print(sss)
}
#
I'd create an empty dataframe prior to the loop.

cata <- c( 3,5,6,8,0, NA)
catb <- c( 1,2,3,4,5,6)
doga <- c(3,5,3,6,4, 0)
dogb <- c(2,4,6,8,10, 12)
rata <- c (NA, 5, 5, 4, 9, 0)
ratb <- c( 1,2,3,4,5,6)
bata <- c( 12, 42,NA, 45, 32, 54)
batb <- c( 13, 15, 17,19,21,23)
id <- c('a', 'b', 'b', 'c', 'a', 'b')
site <- c(1,1,4,4,1,4)
mat1 <-  cbind(cata, catb, doga, dogb, rata, ratb,
bata, batb)
Df <- data.frame(site, id, mat1)
nn <- levels(Df$id)

Df
nn
rate <- c(2,3,4)

Result <- data.frame(matrix(NA,length(nn),4))
for (i in 1: length(nn)) {
dd<- subset(Df, id==nn[i])
scat <- sum(c(dd$cata,dd$catb), na.rm=T)
sdog <- sum(c(dd$doga,dd$dogb), na.rm=T)
srat <- sum(c(dd$rata, dd$ratb), na.rm=T)
sbat <- sum(c(dd$bata,dd$batb), na.rm=T)
sss <- c(scat,sdog, srat,sbat) * rate[i]
Result[i,] <- sss
print(sss)
}
Result
#
My thanks to, in order of the postings appearance at
my reader, Jim Holtman, Andrew Robinson & Neuro
LeSuperH?ros for thre different and very useful
solutions to my problem.  Your help is greatly
appreciated.
--- Neuro LeSuperH?ros <neuro3000 at hotmail.com> wrote: