search for: nameddatalist

Displaying 1 result from an estimated 1 matches for "nameddatalist".

2004 Apr 08
1
Why are Split and Tapply so slow with named vectors, why is a for loop faster than mapply
...for loop accomplishes the job in a few seconds for all 70,000+ records: > splitWithNames <- function(dataVector, nameVector, factorVector){ + dataList <- split(dataVector, factorVector) + nameList <- split(nameVector, factorVector) + listLength <- length(dataList) + namedDataList <- list(NULL) + for(i in 1:listLength){ + x <- dataList[[i]] + names(x) <- nameList[[i]] + namedDataList[[i]] <- x + } + namedDataList + } > system.time(actTimeList <- splitWithNames(actTime, zoneNames, chainId)) [1] 8.04 0.00 9.03 NA...