Good point, Greg. So to handle i as a vector, you'd probably want something like
f <- function(x,i)outer(x,i,"+") -- Bert Bert Gunter Genentech Nonclinical Biostatistics 650-467-7374 -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Greg Snow Sent: Thursday, March 26, 2009 9:54 AM To: Bert Gunter; 'Florin Maican'; [email protected] Subject: Re: [R] programming creating different functions in a loop But wrong questions requiring complicated answers are sometimes more fun :-). One difference though is in my last example, your function will give a different answer for f(1:3, 1:10), but for the simpler cases, yours is probably the better. -- Gregory (Greg) L. Snow Ph.D. Statistical Data Center Intermountain Healthcare [email protected] 801.408.8111 > -----Original Message----- > From: Bert Gunter [mailto:[email protected]] > Sent: Thursday, March 26, 2009 10:33 AM > To: Greg Snow; 'Florin Maican'; [email protected] > Subject: RE: [R] programming creating different functions in a loop > > ... but perhaps even more straightforward is: > > f <- function(i,x)x+i > > Of course, we don't know exactly what the poster is after with his > rather > arcane construction, so this may not suit. But you know the rule: if > the > question requires a complex, tricky answer, it's probably the wrong > question. > > Cheers, > Bert > > Bert Gunter > Genentech Nonclinical Biostatistics > > > -----Original Message----- > From: [email protected] [mailto:r-help-boun...@r- > project.org] On > Behalf Of Greg Snow > Sent: Thursday, March 26, 2009 9:25 AM > To: Florin Maican; [email protected] > Subject: Re: [R] programming creating different functions in a loop > > Anytime that you are tempted to use assign and a loop, you should > consider > using lapply (or sapply) and a list instead. > > Consider this alternative: > > > f <- lapply( 1:3, function(i){ force(i); function(x) x+i} ) > > > > f[[1]](3) > [1] 4 > > f[[2]](10) > [1] 12 > > f[[3]](0) > [1] 3 > > > > sapply( f, function(f) f(1:10) ) > [,1] [,2] [,3] > [1,] 2 3 4 > [2,] 3 4 5 > [3,] 4 5 6 > [4,] 5 6 7 > [5,] 6 7 8 > [6,] 7 8 9 > [7,] 8 9 10 > [8,] 9 10 11 > [9,] 10 11 12 > [10,] 11 12 13 > > Hope this helps, > > -- > Gregory (Greg) L. Snow Ph.D. > Statistical Data Center > Intermountain Healthcare > [email protected] > 801.408.8111 > > > > -----Original Message----- > > From: [email protected] [mailto:r-help-boun...@r- > > project.org] On Behalf Of Florin Maican > > Sent: Thursday, March 26, 2009 9:18 AM > > To: [email protected] > > Subject: [R] programming creating different functions in a loop > > > > Hi > > > > I want to create the following functions in a loop > > > > f1<-function(x){x+1} > > f2<-function(x){x+2} > > f3<-function(x){x+3} > > > > Output f1(2)=3 > > f2(2)=4 > > f3(2)=5 > > > > > > I tried to create the in a loop as bellow but I get wrong on answers > > because the value of i change > > > > for(i in 1:3){ > > assign(paste("f",i,sep="") > > ,function(x) > > x+i > > ) > > } # end for > > > > Output f1(2)=5 > > f2(2)=5 > > f3(2)=5 > > But it is not what I want. The question is how I can > > fix in R the value of "i" in my functions? I tried to use assign() > and > > get(),but I did not manage. > > > > Thanks in advance, > > Florin > > > > -- > > Florin Maican > > ================================== > > > > Department of Economics, > > School of Business, Economics and Law, > > Gothenburg University, Sweden > > ----------------------------------- > > P.O. Box 640 SE-405 30, > > Gothenburg, Sweden > > > > Mobil: +46 76 235 3039 > > Phone: +46 31 786 4866 > > Fax: +46 31 786 4154 > > Home Page: http://maicanfg.googlepages.com/index.html > > E-mail: [email protected] > > ------------------------------------ > > "Not everything that counts can be > > counted, and not everything that can be > > counted counts." > > --- Einstein --- > > > > ______________________________________________ > > [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. ______________________________________________ [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.
