evaluate one variable in an expression with two variables
On Wed, Feb 8, 2012 at 4:02 PM, moli <nirdong at gmail.com> wrote:
I want to evaluate f with the mean=7 ?mean=7 ?f <- ?expression(-(x-mean)^2/2) then get a new expression: ?-(x-7)^2/2 How could I do it? Thanks.
You can leave out the initial as.expression if you don't mind having a call object instead:
as.expression(do.call("substitute", list(f[[1]], list(mean = 7))))
expression(-(x - 7)^2/2)
Statistics & Software Consulting GKX Group, GKX Associates Inc. tel: 1-877-GKX-GROUP email: ggrothendieck at gmail.com