Elasticsearch Term Vectors(词频统计)

向右看齐 2023-06-12 04:12 9阅读 0赞

Term Vectors API returns information and statistics on terms in the fields of a particular document. The document could be stored in the index or artificially provided by the user.

作用：如果想进行全文检索，即从一个词搜索与它相关的文档，这就是Term Vectors。

Term Vectors记录的信息：

doc\_freq索引中有几个记录出现、ttf该词在全部记录中出现的次数、term\_freq在当前文档词的频率

tokens：position位置、start\_offset开始的偏移值、end\_offset结束的偏移值

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hfc245OTk5_size_16_color_FFFFFF_t_70][]

JAVA:

>     @Test
>         public void testTermVectors() throws IOException {
>             
>             TermVectorsRequest request = new TermVectorsRequest("article_index", "15");
>             request.setFields("keyword");
>             request.setFieldStatistics(true); 
>             request.setTermStatistics(true); 
>             request.setPositions(true); 
>             request.setOffsets(true); 
>             request.setPayloads(false); 
>     
>             Map<String, Integer> filterSettings = new HashMap<>();
>             filterSettings.put("max_num_terms", 3);
>             filterSettings.put("min_term_freq", 1);
>             filterSettings.put("max_term_freq", 10);
>             filterSettings.put("min_doc_freq", 1);
>             filterSettings.put("max_doc_freq", 100);
>             filterSettings.put("min_word_length", 1);
>             filterSettings.put("max_word_length", 10);
>     
>             request.setFilterSettings(filterSettings); 
>             TermVectorsResponse response =  client.termvectors(request, RequestOptions.DEFAULT);
>             
>             List<TermVector> termVectorList = response.getTermVectorsList();
>             for(TermVector termVector:termVectorList) {
>                 String fieldName = termVector.getFieldName();
>                 FieldStatistics fieldStatistics = termVector.getFieldStatistics();
>                 List<Term> terms = termVector.getTerms();
>                 for(Term term:terms) {
>                     System.out.println("----term---"+term.getTerm()+"  -DocFreq:-" + term.getDocFreq()+"  -TermFreq:-"+term.getTermFreq()+"--"+term.getTokens());
>                 }
>             }
>         }

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hfc245OTk5_size_16_color_FFFFFF_t_70 1][]

更多代码请参考：[https://github.com/hsn999/Elasticsearch\_7\_springboot\_demo][https_github.com_hsn999_Elasticsearch_7_springboot_demo]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hfc245OTk5_size_16_color_FFFFFF_t_70]: /images/20230531/a00d547af7724f21b731aa9a983ead83.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2hfc245OTk5_size_16_color_FFFFFF_t_70 1]: /images/20230531/b17f4a07c7f64b38af259174bab79375.png
[https_github.com_hsn999_Elasticsearch_7_springboot_demo]: https://github.com/hsn999/Elasticsearch_7_springboot_demo