Incidentally, the OP might want to take a look at ?rle. Michael
On Jul 11, 2012, at 3:42 AM, Sarah Goslee <[email protected]> wrote: > Hi, > > On Wednesday, July 11, 2012, darnold wrote: > >> All, >> >> How come i=1 in the first case, but i=2 in the second case. The second case >> seems to work, but the first case does not. > > > > It dos work: whne your code gets to browser() R calls that function and > passes it the argument given. If you expect that argument to control when > browser() is called, you need to reread ?browser and rethink how you expect > R to work. > > In the second instance, the conditional is checked before R gets to the > browser() command, and it is only called if the condition is met. > > So both examples work as the R designers intend, that's just not how you > thought it should work. > > > Sarah > > > >> David. >> >>> findruns <- function(x,k) { >> + n <- length(x) >> + runs <- NULL >> + for (i in 1:(n-k+1)) { >> + if (all(x[i:(i+k-1)]==1)) runs <- c(runs,i) >> + browser(i>1) >> + } >> + return(runs) >> + } >>> x=c(1,1,0,0,1,1,1) >>> findruns(x,2) >> Called from: findruns(x, 2) >> Browse[1]> i >> [1] 1 >> Browse[1]> Q >>> findruns <- function(x,k) { >> + n <- length(x) >> + runs <- NULL >> + for (i in 1:(n-k+1)) { >> + if (all(x[i:(i+k-1)]==1)) runs <- c(runs,i) >> + if (i>1) browser() >> + } >> + return(runs) >> + } >>> findruns(x,2) >> Called from: findruns(x, 2) >> Browse[1]> i >> [1] 2 >> Browse[1]> >> > > > -- > Sarah Goslee > http://www.stringpage.com > http://www.sarahgoslee.com > http://www.functionaldiversity.org > > [[alternative HTML version deleted]] > > ______________________________________________ > [email protected] 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. ______________________________________________ [email protected] 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.
