Many Thanks Jorge... That was one more way...Is it possible if I can do this without using rep(1:10,each=8) or the grouping....because I feel the number 8 here is fixed... If there is some technique of tracking the position of first 8, then next 8... don't know whether I am clear in conveying...
Thanks, shubha ________________________________ From: Jorge Ivan Velez [mailto:[EMAIL PROTECTED] Sent: Wednesday, July 23, 2008 8:59 PM To: Shubha Vishwanath Karanth Cc: [EMAIL PROTECTED] Subject: Re: [R] sequential sum of a vector... Dear Shubha, Try this: x=1:80 tapply(x,rep(1:10,each=8),sum) 1 2 3 4 5 6 7 8 9 10 36 100 164 228 292 356 420 484 548 612 HTH, Jorge On Wed, Jul 23, 2008 at 10:03 AM, Shubha Vishwanath Karanth <[EMAIL PROTECTED]> wrote: Hi R, Let, x=1:80 I want to sum up first 8 elements of x, then again next 8 elements of x, then again another 8 elements..... So, my new vector should look like: c(36,100,164,228,292,356,420,484,548,612) I used: aggregate(x,list(rep(1:10,each=8)),sum)[-1] or rowsum(x,group=rep(1:10,each=8)) But without grouping, can I achieve the required? Any other ways of doing this? Thanks, Shubha This e-mail may contain confidential and/or privileged i...{{dropped:13}} ______________________________________________ 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. This e-mail may contain confidential and/or privileged i...{{dropped:13}} ______________________________________________ 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.
