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[newbie] aggregating table() results and simplifying code with loop

Rui Barradas 
Hello,

You would get more and better help if you were to break your problem 
into smaller sub-problems.
I am not really sure if this is what you want but here it goes.


inxList <- function(DF, logcover, nYears){
     f <- function(x, n){
         if(any(x)){
             r <- rle(x)
             any(r$lengths[!r$values] == n)
         }else FALSE
     }
     yrs <- lapply(0:5, `+`, seq_len(5))
     inx.list <- lapply(yrs, function(i){apply(logcover[, i], 1, f, 
nYears)})
     inx.list
}

makeCovers <- function(Cover, nYears){
     lcover <- T80[, ycols] == Cover
     inx.list <- inxList(T80[, ycols], lcover, nYears)
     tmp <- rep(NA, length(ws))
     names(tmp) <- ws
     xtb <- do.call(rbind, lapply(seq_along(inx.list), function(ix){
         xt <- xtabs(~ WS, T80[ inx.list[[ix]], c(2, 1 + ix + 1:5) ])
         tmp[names(xt)] <- xt; tmp}))
     colnames(xtb) <- paste("WS", seq_along(ws), sep = "")
     data.frame(xtb, Cover = Cover, Period = seq_along(inx.list))
}

T80 <- read.table("sample.txt", header=TRUE, sep = ";")

ycols <- grep("y", names(T80))
ws <- unique(T80$WS)
covers <- as.character(unique(unlist(T80[ycols])))

result <- lapply( 4:2, function(.n)
         do.call(rbind, lapply(covers, makeCovers, .n)) )
names(result) <- paste("nYears", 4:2, sep = ".")

str(result)
# See the results for 4 years
result[[ "nYears.4" ]]  # or any other number of years


Hope this helps,

Rui Barradas
Em 13-09-2012 14:36, Davide Rizzo escreveu:

Thread (13 messages)

Davide Rizzo aggregating table() results and simplifying code with loop Sep 13 Rui Barradas aggregating table() results and simplifying code with loop Sep 13 John Kane aggregating table() results and simplifying code with loop Sep 15 Davide Rizzo aggregating table() results and simplifying code with loop Sep 15 John Kane aggregating table() results and simplifying code with loop Sep 16 Davide Rizzo aggregating table() results and simplifying code with loop Sep 16 John Kane aggregating table() results and simplifying code with loop Sep 17 Rui Barradas aggregating table() results and simplifying code with loop Sep 17 John Kane aggregating table() results and simplifying code with loop Sep 18 Rui Barradas aggregating table() results and simplifying code with loop Sep 18 Davide Rizzo aggregating table() results and simplifying code with loop Sep 18 Rui Barradas aggregating table() results and simplifying code with loop Sep 18 John Kane aggregating table() results and simplifying code with loop Sep 19