In the function call in 'apply', you are passed the values in the rows: > set.seed(30) > z = matrix(rnorm(10), 5, 2) > apply(z, 1, function(x) sum(z[x,1]*1, z[x,2]*3)) [1] -0.908321 0.000000 0.000000 -5.822442 -5.822442 > z [,1] [,2] [1,] -1.2885182 -1.5113079 [2,] -0.3476894 0.1105080 [3,] -0.5216288 -0.7607962 [4,] 1.2734732 -0.6698970 [5,] 1.8245206 0.2745197 > sum(z[1,1]*1, + z[1,2]*3) [1] -5.822442 > # correct use of apply > apply(z, 1, function(x) x[1]*1 + x[2]*3) [1] -5.82244202 -0.01616527 -2.80401753 -0.73621789 2.64807967 >
On Tue, Apr 28, 2009 at 9:02 PM, megh <megh700...@yahoo.com> wrote: > > Hi all, can you please clarify me what is the wrong with following codes : > > set.seed(30) > z = matrix(rnorm(10), 5, 2) > apply(z, 1, function(x) sum(z[x,1]*1, z[x,2]*3)) > > However I can not get the desired result. For example, "sum(z[1,1]*1, > z[1,2]*3)" gives -5.822442 which is actually correct. Am I missing > something > in apply() function? > > Regards, > > > -- > View this message in context: > http://www.nabble.com/Help-on-apply%28%29-function-tp23288839p23288839.html > Sent from the R help mailing list archive at Nabble.com. > > ______________________________________________ > R-help@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<http://www.r-project.org/posting-guide.html> > and provide commented, minimal, self-contained, reproducible code. > -- Jim Holtman Cincinnati, OH +1 513 646 9390 What is the problem that you are trying to solve? [[alternative HTML version deleted]] ______________________________________________ R-help@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.