.checkMFClasses: Functions to Check the Type of Variables passed to Model Frames
Description
.checkMFClasses
checks if the variables used in a predict
method agree in type with those used for fitting. .MFclass
categorizes variables for this purpose.Usage
.checkMFClasses(cl, m, ordNotOK = FALSE)
.MFclass(x)
.getXlevels(Terms, m)
Arguments
cl
a character vector of class descriptions to match.
ordNotOK
logical: are ordered factors different?
Value
.MFclass
returns a character string, one of "logical"
,
"ordered"
, "factor"
, "numeric"
, "nmatrix.*"
(a numeric matrix with a number of columns appended) or "other"
. .getXlevels
returns a named character vector, or NULL
.Details
For applications involving model.matrix
such as linear models
we do not need to differentiate between ordered factors and factors as
although these affect the coding, the coding used in the fit is
already recorded and imposed during prediction. However, other
applications may treat ordered factors differently:
rpart
does, for example.