.makeAdditiveExpr
Helper functions for makeAdditiveFormula
Description
The functions build the left and right hand sides of the formula produced by makeAdditiveFormula.
You can use these functions directly to build a complicated formula.
Usage
.makeAdditiveExpr(exprs, emptyExprsOutput = 1)
Arguments
exprs |
a character vector of variable names or a list of expressions to use as terms in the output expression.
|
emptyExprsOutput |
the output, if there are no entries in exprs.
|
Details
We do not expect users to need to call these functions. Use the
simpler makeAdditiveFormula when possible.
Value
.makeAdditiveExpr | if exprs has only one entry, then that unaltered entry is returned. |
.makeAdditiveExpr | if exprs has multiple entries, then
an expression of the form expr1 + expr2 + ... is returned. |
.makeCbindExpr | if exprs has only one entry, then that unaltered entry is returned. |
.makeCbindExpr | if exprs has multiple entries, then
an expression of the form cbind(expr1, expr2, ...) is returned. |
See Also
makeAddtiveFormula.
Examples
.makeAdditiveExpr(c("one", "two"))
.makeAdditiveExpr(character())
.makeAdditiveExpr(list(quote(log(one)), quote(sqrt(two))))
.makeCbindExpr(c("one","two"))
.makeCbindExpr(c("one"))