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.
