ffdfsort {ff} | R Documentation |
These functions allow convenient sorting and ordering of collections of (ff) vectors organized in (ffdf) data.frames
dforder(x, ...) dfsort(x, ...) ramdforder(x, ...) ramdfsort(x, ...) ffdforder(x, ...) ffdfsort(x, ...)
x |
a |
... |
further arguments passed to |
the order functions return an (ff) vector of integer order positions, the sort functions return a sorted clone of the (ffdf) input data.frame
Jens Oehlschlägel
sort
, ramsort
or ffsort
order
, ramorder
or fforder
x <- ff(sample(1e5, 1e6, TRUE)) y <- ff(sample(1e5, 1e6, TRUE)) z <- ff(sample(1e5, 1e6, TRUE)) d <- ffdf(x, y, z) d2 <- ffdfsort(d) d2 d d2 <- d[1:2] i <- ffdforder(d2) d[i,] rm(x, y, z, i, d, d2) gc()