# Function for Data Transformations

### Description

Transformations of Response or Input Variables

### Usage

1 2 3 4 |

### Arguments

`data` |
an object of class |

`numeric_trafo` |
a function to by applied to |

`ordered_trafo` |
a function to by applied to |

`factor_trafo` |
a function to by applied to |

`surv_trafo` |
a function to by applied to
elements of class |

`var_trafo` |
an optional named list of functions to be applied to the
corresponding variables in |

`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

1 2 3 4 5 6 | ```
### 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)))
``` |