85 lines
1.8 KiB
Plaintext
85 lines
1.8 KiB
Plaintext
[[analysis-chargroup-tokenizer]]
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=== Character group tokenizer
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++++
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<titleabbrev>Character group</titleabbrev>
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++++
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The `char_group` tokenizer breaks text into terms whenever it encounters a
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character which is in a defined set. It is mostly useful for cases where a simple
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custom tokenization is desired, and the overhead of use of the <<analysis-pattern-tokenizer, `pattern` tokenizer>>
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is not acceptable.
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[discrete]
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=== Configuration
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The `char_group` tokenizer accepts one parameter:
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[horizontal]
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`tokenize_on_chars`::
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A list containing a list of characters to tokenize the string on. Whenever a character
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from this list is encountered, a new token is started. This accepts either single
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characters like e.g. `-`, or character groups: `whitespace`, `letter`, `digit`,
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`punctuation`, `symbol`.
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`max_token_length`::
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The maximum token length. If a token is seen that exceeds this length then
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it is split at `max_token_length` intervals. Defaults to `255`.
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[discrete]
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=== Example output
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[source,console]
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---------------------------
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POST _analyze
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{
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"tokenizer": {
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"type": "char_group",
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"tokenize_on_chars": [
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"whitespace",
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"-",
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"\n"
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]
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},
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"text": "The QUICK brown-fox"
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}
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---------------------------
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returns
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[source,console-result]
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---------------------------
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{
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"tokens": [
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{
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"token": "The",
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"start_offset": 0,
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"end_offset": 3,
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"type": "word",
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"position": 0
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},
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{
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"token": "QUICK",
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"start_offset": 4,
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"end_offset": 9,
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"type": "word",
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"position": 1
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},
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{
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"token": "brown",
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"start_offset": 10,
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"end_offset": 15,
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"type": "word",
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"position": 2
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},
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{
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"token": "fox",
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"start_offset": 16,
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"end_offset": 19,
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"type": "word",
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"position": 3
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}
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]
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}
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---------------------------
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