mirror of
https://github.com/Llewellynvdm/php-ml.git
synced 2024-11-18 19:25:11 +00:00
43 lines
954 B
Markdown
43 lines
954 B
Markdown
|
# Tf-idf Transformer
|
|||
|
|
|||
|
Tf–idf, short for term frequency–inverse document frequency, is a numerical statistic that is intended to reflect how important a word is to a document in a collection or corpus.
|
|||
|
|
|||
|
### Constructor Parameters
|
|||
|
|
|||
|
* $samples (array) - samples for fit tf-idf model
|
|||
|
|
|||
|
```
|
|||
|
use Phpml\FeatureExtraction\TfIdfTransformer;
|
|||
|
|
|||
|
$samples = [
|
|||
|
[1, 2, 4],
|
|||
|
[0, 2, 1]
|
|||
|
];
|
|||
|
|
|||
|
$transformer = new TfIdfTransformer($samples);
|
|||
|
```
|
|||
|
|
|||
|
### Transformation
|
|||
|
|
|||
|
To transform a collection of text samples use `transform` method. Example:
|
|||
|
|
|||
|
```
|
|||
|
use Phpml\FeatureExtraction\TfIdfTransformer;
|
|||
|
|
|||
|
$samples = [
|
|||
|
[0 => 1, 1 => 1, 2 => 2, 3 => 1, 4 => 0, 5 => 0],
|
|||
|
[0 => 1, 1 => 1, 2 => 0, 3 => 0, 4 => 2, 5 => 3],
|
|||
|
];
|
|||
|
|
|||
|
$transformer = new TfIdfTransformer($samples);
|
|||
|
$transformer->transform($samples);
|
|||
|
|
|||
|
/*
|
|||
|
$samples = [
|
|||
|
[0 => 0, 1 => 0, 2 => 0.602, 3 => 0.301, 4 => 0, 5 => 0],
|
|||
|
[0 => 0, 1 => 0, 2 => 0, 3 => 0, 4 => 0.602, 5 => 0.903],
|
|||
|
];
|
|||
|
*/
|
|||
|
|
|||
|
```
|