Dear List I am getting a problem when using "eval(parse)". Code below sketchs what I am trying to do:
For each row of a N*K dataframe (I use a 2*2 dataframe in the example below), applying a number of functions and get the outputs (two functions, "sum" and "var" are used in the example below). The problem is eval(parse(text="sum(para)")) works fine but not when "sum" is replaced by "var". in the later case, a matrix instead of a number is returned. Any suggestion highly appreciated. Thank you #===================================================The function myloop <-function(datfra,funs) { rows<-dim(datfra)[1]; totfunnum<-length(funs); for (i in 1:rows) { vec<-datfra[i,]; for(k in 1:totfunnum) { print(funs[k]); x<-eval(parse(text=funs[k])); print(x); } } } #================================================Experiemental run workport<-data.frame(matrix(1:4,2,2)) funs<-c("sum(vec,na.rm=T)","var(vec,na.rm=T)") myloop(workport,funs) #================================================ Outputs of the Experimental run [1] "sum(vec,na.rm=T)" [1] 4 [1] "var(vec,na.rm=T)" X1 X2 X1 NA NA X2 NA NA [1] "sum(vec,na.rm=T)" [1] 6 [1] "var(vec,na.rm=T)" X1 X2 X1 NA NA X2 NA NA ______________________________________________ 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.