Hey All, So, I am confused how exactly to use nesting loop functions in R to spit out data frames. I've managed to create a working function for my data set that generates a data frame for a given set of Year i and Location j; but how would I do it for all Years and Locations?
Here is my working function: test<-function(i,j){ a<-x[which(x$Year==i & x$Location==j),] b<-as.data.frame(as.matrix(table(a$Species,a$Species))) c<-b[-which(b$Var1==b$Var2),-3] c$Year<-i; c$Location<-j return(c) } Where, x is a dataframe that looks like the following: > head(x,n=20) Year Location Species 66 1998 PIPE_7 ACMI2 67 1998 PIPE_7 AMAR2 68 1998 PIPE_7 AMCA6 69 1998 PIPE_7 ANCY 70 1998 PIPE_7 ASVE 71 1998 PIPE_7 BOCU 72 1998 PIPE_7 CIFL 73 1998 PIPE_7 DAPU5 74 1998 PIPE_7 DICHANTHEL 75 1998 PIPE_7 GABO2 76 1998 PIPE_7 HEHE5 77 1998 PIPE_7 LIAS 78 1998 PIPE_7 LIPY 79 1998 PIPE_7 PAVI2 80 1998 PIPE_7 PHPI 81 1998 PIPE_7 PHVI5 82 1998 PIPE_7 RAPI 83 1998 PIPE_7 SOCA6 84 1998 PIPE_7 VIPE2 85 1998 PIPE_7 ZIAU and when feeding x into my function "test" with the parameters i = 1998 and j = "PIPE_7", I get the following dataframe, c: > head(test(1998,"PIPE_7"),n=20) Var1 Var2 Year Location 2 AMAR2 ACMI2 1998 PIPE_7 3 AMCA6 ACMI2 1998 PIPE_7 4 ANCY ACMI2 1998 PIPE_7 5 ASVE ACMI2 1998 PIPE_7 6 BOCU ACMI2 1998 PIPE_7 7 CIFL ACMI2 1998 PIPE_7 8 DAPU5 ACMI2 1998 PIPE_7 9 DICHANTHEL ACMI2 1998 PIPE_7 10 GABO2 ACMI2 1998 PIPE_7 11 HEHE5 ACMI2 1998 PIPE_7 12 LIAS ACMI2 1998 PIPE_7 13 LIPY ACMI2 1998 PIPE_7 14 PAVI2 ACMI2 1998 PIPE_7 15 PHPI ACMI2 1998 PIPE_7 16 PHVI5 ACMI2 1998 PIPE_7 17 RAPI ACMI2 1998 PIPE_7 18 SOCA6 ACMI2 1998 PIPE_7 19 VIPE2 ACMI2 1998 PIPE_7 20 ZIAU ACMI2 1998 PIPE_7 21 ACMI2 AMAR2 1998 PIPE_7 I have searched through the R-help archives for hints, which have not been successful in answering my question. As a new user to R and programming languages, I truly appreciate your help and thank you for your patience. Thanks in advance for your response, Lanna Jin ----- Lanna Jin lanna...@gmail.com 510-898-8525 -- View this message in context: http://n4.nabble.com/nested-looping-functions-and-dataframes-tp1595166p1595166.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 and provide commented, minimal, self-contained, reproducible code.