---
name: "Plucene::Analysis::PorterStemFilter"
section: "3pm"
platform: "linux"
package: "libplucene-perl"
version: "1.25-5"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Plucene::Analysis::PorterStemFilter"
---

# Plucene::Analysis::PorterStemFilter(3pm)

Porter stemming on the token stream

## NAME

Plucene::Analysis::PorterStemFilter - Porter stemming on the token stream

## SYNOPSIS

```
        # isa Plucene::Analysis:::TokenFilter

        my $token = $porter_stem_filter->next;
```

## DESCRIPTION

This class transforms the token stream as per the Porter stemming algorithm.

Note: the input to the stemming filter must already be in lower case, so you  will need to use LowerCaseFilter or LowerCaseTokenizer farther down the  Tokenizer chain in order for this to work properly!

The Porter Stemmer implements Porter Algorithm for normalization of English  words by stripping their extensions and is used to generalize the searches.  For example, the Porter algorithm maps both 'search' and 'searching'  (as well as 'searchnessing') to 'search' such that a query for 'search' will  also match documents that contains the word 'searching'.

Note that the Porter algorithm is specific to the English language and may give  unpredictable results for other languages. Also, make sure to use the same  analyzer during the indexing and the searching.

You can find more information on the Porter algorithm at  www.tartarus.org/~martin/PorterStemmer.

A nice online demonstration of the Porter algorithm is available at  www.scs.carleton.ca/~dquesnel/java/stuff/PorterApplet.html.

## METHODS

### next

```
        my $token = $porter_stem_filter->next;
```

Returns the next input token, after being stemmed.