tag:blogger.com,1999:blog-6576681508814660796.post2718852050935862271..comments2011-02-19T17:59:22.489-05:00Comments on Enterprise Software Doesn't Have to Suck: Stata or R - How to create dynamic variables in R?...prasoonsharmanoreply@blogger.comBlogger1125tag:blogger.com,1999:blog-6576681508814660796.post-583140782264969702011-02-19T17:59:22.489-05:002011-02-19T17:59:22.489-05:00Assuming popA1989, popB1989 ... already exist in d...Assuming popA1989, popB1989 ... already exist in data.frame dat.<br /><br />require(stringr)<br />pop <- LETTERS[1:4]<br />years <- 1990:2000<br /><br />for(i in years){<br /> dat[str_c(str_c("pop",pop),i)] <- dat[str_c(str_c("pop",pop),i-1)]*(1+dat[rep(str_c("trend",i-1),length(pop))])<br />}Anonymousnoreply@blogger.com