OpenSearch/docs/reference/analysis/analyzers/stop-analyzer.asciidoc

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[[analysis-stop-analyzer]]
=== Stop analyzer
++++
<titleabbrev>Stop</titleabbrev>
++++
The `stop` analyzer is the same as the <<analysis-simple-analyzer,`simple` analyzer>>
but adds support for removing stop words. It defaults to using the
`_english_` stop words.
[discrete]
=== Example output
[source,console]
---------------------------
POST _analyze
{
"analyzer": "stop",
"text": "The 2 QUICK Brown-Foxes jumped over the lazy dog's bone."
}
---------------------------
/////////////////////
[source,console-result]
----------------------------
{
"tokens": [
{
"token": "quick",
"start_offset": 6,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "brown",
"start_offset": 12,
"end_offset": 17,
"type": "word",
"position": 2
},
{
"token": "foxes",
"start_offset": 18,
"end_offset": 23,
"type": "word",
"position": 3
},
{
"token": "jumped",
"start_offset": 24,
"end_offset": 30,
"type": "word",
"position": 4
},
{
"token": "over",
"start_offset": 31,
"end_offset": 35,
"type": "word",
"position": 5
},
{
"token": "lazy",
"start_offset": 40,
"end_offset": 44,
"type": "word",
"position": 7
},
{
"token": "dog",
"start_offset": 45,
"end_offset": 48,
"type": "word",
"position": 8
},
{
"token": "s",
"start_offset": 49,
"end_offset": 50,
"type": "word",
"position": 9
},
{
"token": "bone",
"start_offset": 51,
"end_offset": 55,
"type": "word",
"position": 10
}
]
}
----------------------------
/////////////////////
The above sentence would produce the following terms:
[source,text]
---------------------------
[ quick, brown, foxes, jumped, over, lazy, dog, s, bone ]
---------------------------
[discrete]
=== Configuration
The `stop` analyzer accepts the following parameters:
[horizontal]
`stopwords`::
A pre-defined stop words list like `_english_` or an array containing a
list of stop words. Defaults to `_english_`.
`stopwords_path`::
The path to a file containing stop words. This path is relative to the
Elasticsearch `config` directory.
See the <<analysis-stop-tokenfilter,Stop Token Filter>> for more information
about stop word configuration.
[discrete]
=== Example configuration
In this example, we configure the `stop` analyzer to use a specified list of
words as stop words:
[source,console]
----------------------------
PUT my-index-000001
{
"settings": {
"analysis": {
"analyzer": {
"my_stop_analyzer": {
"type": "stop",
"stopwords": ["the", "over"]
}
}
}
}
}
POST my-index-000001/_analyze
{
"analyzer": "my_stop_analyzer",
"text": "The 2 QUICK Brown-Foxes jumped over the lazy dog's bone."
}
----------------------------
/////////////////////
[source,console-result]
----------------------------
{
"tokens": [
{
"token": "quick",
"start_offset": 6,
"end_offset": 11,
"type": "word",
"position": 1
},
{
"token": "brown",
"start_offset": 12,
"end_offset": 17,
"type": "word",
"position": 2
},
{
"token": "foxes",
"start_offset": 18,
"end_offset": 23,
"type": "word",
"position": 3
},
{
"token": "jumped",
"start_offset": 24,
"end_offset": 30,
"type": "word",
"position": 4
},
{
"token": "lazy",
"start_offset": 40,
"end_offset": 44,
"type": "word",
"position": 7
},
{
"token": "dog",
"start_offset": 45,
"end_offset": 48,
"type": "word",
"position": 8
},
{
"token": "s",
"start_offset": 49,
"end_offset": 50,
"type": "word",
"position": 9
},
{
"token": "bone",
"start_offset": 51,
"end_offset": 55,
"type": "word",
"position": 10
}
]
}
----------------------------
/////////////////////
The above example produces the following terms:
[source,text]
---------------------------
[ quick, brown, foxes, jumped, lazy, dog, s, bone ]
---------------------------
[discrete]
=== Definition
It consists of:
Tokenizer::
* <<analysis-lowercase-tokenizer,Lower Case Tokenizer>>
Token filters::
* <<analysis-stop-tokenfilter,Stop Token Filter>>
If you need to customize the `stop` 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
`stop` analyzer and you can use it as a starting point for further
customization:
[source,console]
----------------------------------------------------
PUT /stop_example
{
"settings": {
"analysis": {
"filter": {
"english_stop": {
"type": "stop",
"stopwords": "_english_" <1>
}
},
"analyzer": {
"rebuilt_stop": {
"tokenizer": "lowercase",
"filter": [
"english_stop" <2>
]
}
}
}
}
}
----------------------------------------------------
// TEST[s/\n$/\nstartyaml\n - compare_analyzers: {index: stop_example, first: stop, second: rebuilt_stop}\nendyaml\n/]
<1> The default stopwords can be overridden with the `stopwords`
or `stopwords_path` parameters.
<2> You'd add any token filters after `english_stop`.