Hi, Would this do as an alternative syntax?
g1 <- quote(1/Tm) mat <- list(0, bquote(f1*s1*.(g1))) vals <- data.frame(f1=1, s1=.5, Tm=2) sapply(mat, eval, vals) HTH, baptiste On 29 January 2010 17:51, Jennifer Young <jennifer.yo...@math.mcmaster.ca> wrote: > Hallo > > I'm having trouble figuring out how to evaluate an expression when one of > the variables in the expression is defined separately as a sub expression. > Here's a simplified example > > mat <- expression(0, f1*s1*g1) # vector of formulae > g1 <- expression(1/Tm) # expansion of the definition of g1 > vals <- data.frame(f1=1, s1=.5, Tm=2) # one set of possible values for > variables > > before adding this sub expression I was using the following to evaluate "mat" > > sapply(mat, eval, vals) > > Obviously I could manually substitute in 1/Tm for each g1 in the > definition of "mat", but the actual expression vector is much longer, and > the sub expression more complicated. Also, the subexpression is often > adjusted for different scenarios. Is there a simple way of changing this > or redefining "mat" so that I can define "g1" like a macro to be used in > the expression vector. > > Thanks! > Jennifer > > ______________________________________________ > 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. > ______________________________________________ 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.
