| get.var {mgcv} | R Documentation |
Get named variable or evaluate expression from list or data.frame
Description
This routine takes a text string and a data frame or list. It first sees if the
string is the name of a variable in the data frame/ list. If it is then the value of this variable is returned.
Otherwise the routine tries to evaluate the expression within the data.frame/list (but nowhere else) and if
successful returns the result. If neither step works then NULL is returned. The routine is useful for
processing gam formulae. If the variable is a matrix then it is coerced to a numeric vector, by default.
Usage
get.var(txt,data,vecMat=TRUE)
Arguments
txt |
a text string which is either the name of a variable in |
data |
A data frame or list. |
vecMat |
Should matrices be coerced to numeric vectors? |
Value
The evaluated variable or NULL. May be coerced to a numeric vector if it's a matrix.
Author(s)
Simon N. Wood simon.wood@r-project.org
References
https://www.maths.ed.ac.uk/~swood34/
See Also
Examples
require(mgcv)
y <- 1:4;dat<-data.frame(x=5:10)
get.var("x",dat)
get.var("y",dat)
get.var("x==6",dat)
dat <- list(X=matrix(1:6,3,2))
get.var("X",dat)