[R] Evaluating f(x(2,3)) on a function f- function(a,b){a+b}
Dear list I have a function and a vector, say f - function(a,b){a+b} x - c(2,3) I want to evaluate f on x in the sense of computing f(x[1],x[2]). I would like it to be so that I can write f(x). (I know I can write a wrapper function g - function(x){f(x[1],x[2])}, but this is not really what I am looking for). Is there a general way doing this (programmatically)? (E.g. by unpacking the elements of x and putting them in the right places when calling f...) I've looked under formals, alist etc. but so far without luck. Regards Søren [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch 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.
Re: [R] Evaluating f(x(2,3)) on a function f- function(a,b){a+b}
Try this: do.call(f, as.list(x)) On 8/22/07, Søren Højsgaard [EMAIL PROTECTED] wrote: Dear list I have a function and a vector, say f - function(a,b){a+b} x - c(2,3) I want to evaluate f on x in the sense of computing f(x[1],x[2]). I would like it to be so that I can write f(x). (I know I can write a wrapper function g - function(x){f(x[1],x[2])}, but this is not really what I am looking for). Is there a general way doing this (programmatically)? (E.g. by unpacking the elements of x and putting them in the right places when calling f...) I've looked under formals, alist etc. but so far without luck. Regards Søren [[alternative HTML version deleted]] __ R-help@stat.math.ethz.ch 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@stat.math.ethz.ch 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.
Re: [R] Evaluating f(x(2,3)) on a function f- function(a,b){a+b}
On 8/22/07, Søren Højsgaard [EMAIL PROTECTED] wrote: I have a function and a vector, say f - function(a,b){a+b} x - c(2,3) I want to evaluate f on x in the sense of computing f(x[1],x[2]). I would like it to be so that I can write f(x). (I know I can write a wrapper function g - function(x){f(x[1],x[2])}, but this is not really what I am looking for). Is there a general way doing this (programmatically)? (E.g. by unpacking the elements of x and putting them in the right places when calling f...) I've looked under formals, alist etc. but so far without luck. I hope that the following helps: f - function(x) {sum(x)} f(c(2,3)) [1] 5 f(c(2,3,5)) [1] 10 Paul __ R-help@stat.math.ethz.ch 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.