R: Function for Data Transformations

Transformations {party} | R Documentation

## Function for Data Transformations

### Description

Transformations of Response or Input Variables

### Usage

    ptrafo(data, numeric_trafo = id_trafo, factor_trafo = ff_trafo,
        ordered_trafo = of_trafo, surv_trafo = logrank_trafo,
        var_trafo = NULL)
    ff_trafo(x)

### Arguments

`data` | an object of class `data.frame`.
`numeric_trafo` | a function to by applied to `numeric` elements of `data` returning a matrix with `nrow(data)` rows and an arbitrary number of columns.
`ordered_trafo` | a function to by applied to `ordered` elements of `data` returning a matrix with `nrow(data)` rows and an arbitrary number of columns (usually some scores).
`factor_trafo` | a function to by applied to `factor` elements of `data` returning a matrix with `nrow(data)` rows and an arbitrary number of columns (usually a dummy or contrast matrix).
`surv_trafo` | a function to by applied to elements of class `Surv` of `data` returning a matrix with `nrow(data)` rows and an arbitrary number of columns.
`var_trafo` | an optional named list of functions to be applied to the corresponding variables in `data`.
`x` | a factor

### Details

`trafo` applies its arguments to the elements of `data` according to the classes of the elements. See `Transformations` for more documentation and examples.

In the presence of missing values, one needs to make sure that all user-supplied functions deal with that.

### Value

A named matrix with `nrow(data)` rows and arbitrary number of columns.

### Examples

      ### rank a variable
      ptrafo(data.frame(y = 1:20),
             numeric_trafo = function(x) rank(x, na.last = "keep"))

      ### dummy coding of a factor
      ptrafo(data.frame(y = gl(3, 9)))

[Package party version 1.3-7 Index]