How to apply calculations in "formula" to "data frame"

`model.matrix` was what I was looking for.

Thanks,
S?ren
On 28.03.2017, at 16:57, peter dalgaard <pdalgd at gmail.com> wrote:

On 28 Mar 2017, at 16:14 , S?ren Vogel <soeren.vogel at posteo.ch> wrote:

Hello

Ho can I apply a formula to a data frame?

That would depend on whether the formula has any special interpretation.

If if is just an elementary expression, then it would be like 

eval(For1[[3]], Data, environment(For1))

but you are using "." to represent... what exactly?

One possibility is model.matrix(For1, Data)

but I'm not at all sure that that is what you want.

-pd

library("formula.tools")
Data <- data.frame("v1" = rnorm(31), "v2" = runif(31), "v3" = sample(1:7, 31, repl=T), "v4" = rlnorm(31))
For1 <- as.formula(v1 ~ .^3)
Lhs <- Data[, formula.tools::lhs.vars(formula)]
Rhs <- apply_formula_to_data_frame_and_return_result(data, formula) # ???

Thank you,
S?ren

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How to apply calculations in "formula" to "data frame"

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