On Fri, Dec 31, 2010 at 1:03 PM, Paolo Rossi <statmailingli...@googlemail.com> wrote: > Hi Everyone, > > quick question before the end of the year. > > I have soem indices to select data from a bigger sample. I want to select n > days before each index and n days after the index. Any clever way to do it. > A for loop would do but I wanted to know if there is a moreR-friendly way to > approach this > > Example > # InitialIndices > i2 = (90, 190, 290) > > # Indices I want to end up with > i3 = c(85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 185, 186, 187, 188, 189, > 190, 191, 192, 193, 194, 195 > 285, 286, 287, 288, 289, 290, 291, 292, 293, 294, 295) > # A way to get Final Indices > SampleWidth > i3 = c(i2) > for (j in seq(1, SampleWidth )) { > i3 = c(i3, i2 + j ) > i3 = c(i3, i2 - j ) > }
Try this: n <- 5 c(sapply(i2, function(x) seq(x - n, x + n))) -- Statistics & Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.com ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.