elasticsearch/docs/reference/text-analysis/analysis-fingerprint-analyzer.md
Colleen McGinnis 9bcd59596d
[docs] Prepare for docs-assembler (#125118)
* reorg files for docs-assembler and create toc.yml files

* fix build error, add redirects

* only toc

* move images
2025-03-20 12:09:12 -05:00

120 lines
3.3 KiB
Markdown

---
navigation_title: "Fingerprint"
mapped_pages:
- https://www.elastic.co/guide/en/elasticsearch/reference/current/analysis-fingerprint-analyzer.html
---
# Fingerprint analyzer [analysis-fingerprint-analyzer]
The `fingerprint` analyzer implements a [fingerprinting algorithm](https://github.com/OpenRefine/OpenRefine/wiki/Clustering-In-Depth#fingerprint) which is used by the OpenRefine project to assist in clustering.
Input text is lowercased, normalized to remove extended characters, sorted, deduplicated and concatenated into a single token. If a stopword list is configured, stop words will also be removed.
## Example output [_example_output]
```console
POST _analyze
{
"analyzer": "fingerprint",
"text": "Yes yes, Gödel said this sentence is consistent and."
}
```
The above sentence would produce the following single term:
```text
[ and consistent godel is said sentence this yes ]
```
## Configuration [_configuration_2]
The `fingerprint` analyzer accepts the following parameters:
`separator`
: The character to use to concatenate the terms. Defaults to a space.
`max_output_size`
: The maximum token size to emit. Defaults to `255`. Tokens larger than this size will be discarded.
`stopwords`
: A pre-defined stop words list like `_english_` or an array containing a list of stop words. Defaults to `_none_`.
`stopwords_path`
: The path to a file containing stop words.
See the [Stop Token Filter](/reference/text-analysis/analysis-stop-tokenfilter.md) for more information about stop word configuration.
## Example configuration [_example_configuration_2]
In this example, we configure the `fingerprint` analyzer to use the pre-defined list of English stop words:
```console
PUT my-index-000001
{
"settings": {
"analysis": {
"analyzer": {
"my_fingerprint_analyzer": {
"type": "fingerprint",
"stopwords": "_english_"
}
}
}
}
}
POST my-index-000001/_analyze
{
"analyzer": "my_fingerprint_analyzer",
"text": "Yes yes, Gödel said this sentence is consistent and."
}
```
The above example produces the following term:
```text
[ consistent godel said sentence yes ]
```
## Definition [_definition]
The `fingerprint` tokenizer consists of:
Tokenizer
: * [Standard Tokenizer](/reference/text-analysis/analysis-standard-tokenizer.md)
Token Filters (in order)
: * [Lower Case Token Filter](/reference/text-analysis/analysis-lowercase-tokenfilter.md)
* [ASCII folding](/reference/text-analysis/analysis-asciifolding-tokenfilter.md)
* [Stop Token Filter](/reference/text-analysis/analysis-stop-tokenfilter.md) (disabled by default)
* [Fingerprint](/reference/text-analysis/analysis-fingerprint-tokenfilter.md)
If you need to customize the `fingerprint` analyzer beyond the configuration parameters then you need to recreate it as a `custom` analyzer and modify it, usually by adding token filters. This would recreate the built-in `fingerprint` analyzer and you can use it as a starting point for further customization:
```console
PUT /fingerprint_example
{
"settings": {
"analysis": {
"analyzer": {
"rebuilt_fingerprint": {
"tokenizer": "standard",
"filter": [
"lowercase",
"asciifolding",
"fingerprint"
]
}
}
}
}
}
```