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Lambda Function#

Run a stateless lambda function over the samples in a dataset. The function receives three arguments - the sample to be transformed, its row offset in the dataset, and a user-defined outside context variable that can be used to hold state.

Note: If the transformation results in a change in dimensionality, the change must be consistent for each sample.

Interfaces: Transformer

Compatibility Depends on callback function


# Param Default Type Description
1 callback callable The function to call over the samples in the dataset.
2 context null mixed The outside context that gets injected into the callback function on each call.


use Rubix\ML\Transformers\LambdaFunction;

$callback = function (&$sample, $offset, $context) {
    $sample[] = log1p($sample[3]);

$transformer = new LambdaFunction($callback, 'example context');

Additional Methods#

This transformer does not have any additional methods.