[R] Aggregate and cross tabulation

R-helpers: I have a data frame containing 4 factor variables (let's say A,B,C, and D) and 1 numerical variable (N). I would like to produce a cross-tabulated data frame in which A,B,C are individual columns, each factor of D is its own column, and the field is calculated as a given

Re: [R] Aggregate and cross tabulation

FIRST: PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code. If you expect an answer, please provide the data. Here is one way of doing it: N - 30 x - data.frame(A=sample(1:3, N, TRUE), B=sample(1:2, N,