Re: [R] How to remove double for loop?

From: <Bill.Venables_at_csiro.au>
Date: Wed, 19 Mar 2008 22:37:19 +1000


One possibility might be

Val <- outer(0:n, 0:n, function(i, j) ifelse(i <= j, u^i*d^(j-i), 0))

-----Original Message-----
From: r-help-bounces_at_r-project.org [mailto:r-help-bounces_at_r-project.org] On Behalf Of Jonas Malmros
Sent: Wednesday, 19 March 2008 9:24 PM
To: r-help_at_r-project.org
Subject: [R] How to remove double for loop?

Hello everyone.

I use double for loops to fill in matrices, but there are surely better (and computationally faster) ways to perform that task. Could someone show me, given the following example of a double for loop, how this could be done? It is much easier to learn by examples.

Val <- matrix(0, nrow=n+1, ncol=n+1)
for( i in 0:n){

    for(j in 0:i){

        Val[j+1, i+1] <- u^j*d^(i-j)
    }

}

Thank you in advance!

-- 
Jonas Malmros


______________________________________________
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.
______________________________________________
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 Wed 19 Mar 2008 - 12:40:02 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 Wed 19 Mar 2008 - 13:30:22 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.

list of date sections of archive