Expression evaluation

Assign and retrieve variables on the fly

Assign/Get

The assign() function is the equivalent of the arrow '<-' operator.

assign("x", mean(runif(10)))
get("x")

## [1] 0.5767

patientid <- "10"
assign(paste0("treatment", patientid), sample(c("control", "treatment"), 1))
treatment10

## [1] "treatment"

Eval

This function is able to evaluate a character string as if it was direct R code.

eval(parse(text=paste0("i <- ", "\"lots lots lots\"")))
i

## [1] "lots lots lots"

This work by Celine Hernandez is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.