From: Kevin Ummel <kevinummel_at_gmail.com>

Date: Thu, 14 Apr 2011 14:34:44 -0500

R-help_at_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. Received on Thu 14 Apr 2011 - 20:17:06 GMT

Date: Thu, 14 Apr 2011 14:34:44 -0500

Take vector x and a subset y:

x=1:10

y=c(4,5,7,9)

For each value in 'x', I want to know how many elements in 'y' are less than 'x'.

An example would be:

sapply(x,FUN=function(i) {length(which(y<i))}) [1] 0 0 0 0 1 2 2 3 3 4

But this solution is far too slow when x and y have lengths in the millions.

I'm certain an elegant (and computationally efficient) solution exists, but I'm in the weeds at this point.

Take two vectors x and y, where y is a subset of x:

[[alternative HTML version deleted]]

R-help_at_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. Received on Thu 14 Apr 2011 - 20:17:06 GMT

Archive maintained by Robert King, hosted by
the discipline of
statistics at the
University of Newcastle,
Australia.

Archive generated by hypermail 2.2.0, at Thu 14 Apr 2011 - 22:40:31 GMT.

*
Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help.
Please read the posting
guide before posting to the list.
*