getFpTransforms: Internal functions to handle FP transforms.
Description
Transform a variable according to FP transformation formula and attach
proper names to the resulting design matrix. The binary function
bt is the Box-Tidwell transform.
Usage
x %bt% pow
getFpTransforms(vec, powers, center=TRUE)
getTransformName(name, pow)
Arguments
x
numeric vector
pow
one single power (not vectorized in this argument)
vec
positive (== already shifted and scaled) column vector (!) with
proper colname
powers
power vector with at least one element
center
should the columns be centered around zero? (default)