search for: fischerid

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

2005 Oct 13
3
aggregate slow with many rows - alternative?
...(33'000 rows) where the function is really slow (nothing happened in half an hour). Does anybody know of other functions that I could use? Thanks, Hans-Peter -------------- dat <- data.frame( Datum = c( 32586, 32587, 32587, 32625, 32656, 32656, 32656, 32672, 32672, 32699 ), FischerID = c( 58395, 58395, 58395, 88434, 89953, 89953, 89953, 64395, 62896, 62870 ), Anzahl = c( 2, 2, 1, 1, 2, 1, 7, 1, 1, 2 ) ) f <- function(x) data.frame( Datum = x[1,1], FischerID = x[1,2], Anzahl = sum( x[,3] ), Cnt = dim( x )[1] ) t.a <- do.call("rbind", by(dat, dat[,1:...