Sorry!! meant: apply(array,1:2,sum)/dim(array)[3] M
On Wed, Oct 5, 2011 at 4:31 PM, R. Michael Weylandt <michael.weyla...@gmail.com> wrote: > Actually, this may just be a typo in your first post, but if you > actually want to do this calculation: > > (array[,,1] + array[,,2] + array[,,3] + array[,,4] + array[,,5] + > array[,,6] + array[,,7] + array[,,8]) / 8 > > Wouldn't this work? > > apply(array,3,sum)/dim(array)[3] > > > On Wed, Oct 5, 2011 at 4:22 PM, R. Michael Weylandt > <michael.weyla...@gmail.com> wrote: >> Didn't three of us give you a function (in various flavors) that would >> do the mean for variable inputs, reading them from a list? (Though >> David's was admittedly much cooler than mine!) >> >> Anyways, look into parse(text=do) with eval() if you want to go the >> string route. >> >> Michael >> >> On Wed, Oct 5, 2011 at 4:14 PM, Martin Batholdy <batho...@googlemail.com> >> wrote: >>> Dear R-group, >>> >>> >>> is there a way to perform calculations that are defined in a string format? >>> >>> >>> for example I have different variables: >>> >>> x1 <- 3 >>> x2 <- 1 >>> x4 <- 1 >>> >>> and a string-variable: >>> >>> do <- 'x1 + x2 + x3' >>> >>> >>> Is there any way to perform what the variable 'do'-describes >>> (just like the formula-element but more elemental)? >>> >>> >>> >>> Perhaps my idea to solve my problem is a little bit strange. >>> >>> >>> My general problem is, that I have to do arithmetics for which there seems >>> to be no function available that I can apply in order to be more flexible. >>> >>> >>> To be precise, I have to add up three dimensional arrays. >>> >>> I can do that like this (as someone suggested on this help-list – thanks >>> for that!): >>> >>> (array[,,1] + array[,,2] + array[,,3]) / 3 >>> >>> >>> However in my case it can happen that at some point, I don't have to add 3 >>> but 8 'array-slices' >>> (or 10 or x). >>> >>> And I don't want to manually expand the above statement to: >>> >>> (array[,,1] + array[,,2] + array[,,3] + array[,,4] + array[,,5] + >>> array[,,6] + array[,,7] + array[,,8]) / 8 >>> >>> (ok, now I have done it ;) >>> >>> >>> >>> So, my thinking was that I can easily expand and change a string (with the >>> paste-function / repeat-function etc.). >>> But how can I expand a mathematical statement? >>> >>> >>> thanks for any suggestions! >>> ______________________________________________ >>> 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. >>> >> > ______________________________________________ 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.