R: Data preparator for LightGBM datasets (integer)

lgb.prepare2 {lightgbm} | R Documentation

## Data preparator for LightGBM datasets (integer)

### Description

Attempts to prepare a clean dataset to prepare to put in a `lgb.Dataset`. Factors and characters are converted to numeric (specifically: integer). Please use `lgb.prepare_rules2` if you want to apply this transformation to other datasets. This is useful if you have a specific need for integer dataset instead of numeric dataset. Note that there are programs which do not support integer-only input. Consider this as a half memory technique which is dangerous, especially for LightGBM.

### Usage

    lgb.prepare2(data)

### Arguments

`data` | A data.frame or data.table to prepare.

### Value

The cleaned dataset. It must be converted to a matrix format (`as.matrix`) for input in `lgb.Dataset`.

### Examples

    library(lightgbm)
    data(iris)

    str(iris)

    # Convert all factors/chars to integer
    str(lgb.prepare2(data = iris))

    ## Not run:
    # When lightgbm package is installed, and you do not want to load it
    # You can still use the function!
    lgb.unloader()
    str(lightgbm::lgb.prepare2(data = iris))
    # 'data.frame':	150 obs. of  5 variables:
    # $ Sepal.Length: num  5.1 4.9 4.7 4.6 5 5.4 4.6 5 4.4 4.9 ...
    # $ Sepal.Width : num  3.5 3 3.2 3.1 3.6 3.9 3.4 3.4 2.9 3.1 ...
    # $ Petal.Length: num  1.4 1.4 1.3 1.5 1.4 1.7 1.4 1.5 1.4 1.5 ...
    # $ Petal.Width : num  0.2 0.2 0.2 0.2 0.2 0.4 0.3 0.2 0.2 0.1 ...
    # $ Species     : int  1 1 1 1 1 1 1 1 1 1 ...

    ## End(Not run)

[Package lightgbm version 2.3.1 Index]