External characteristics: mainly refers to the title (title), author's name, publishing house, report number, patent number, etc. Different documents are arranged according to the word order of article title and author's name, or according to the numerical order of report number and patent number, and the retrieval language that meets the needs of users is formed through the retrieval method of article title, author and number.
Document retrieval language is a special language used to process, store and retrieve document information, and it is a concept identification system that expresses a series of concepts that summarize the content of document information and the content of retrieval subject and their relationship.
Extended data
The main functions of retrieval language are as follows:
1. features: index the information content and appearance features of documents to ensure the consistency of documents represented by different indexers.
2. Relevance: focus or reveal the relevance of the same and related literature information.
3. Ordered retrieval: it is required to centralize, systematize and organize the storage of literature information, so as to facilitate the orderly retrieval by the searcher according to a certain arrangement order.
4. Consistency: it is convenient to compare the consistency of indexing words and retrieval words, to ensure the consistency of different searchers expressing the same document content, and to ensure the consistency of searchers and indexers expressing the same document content.
5. Maximum precision: Ensure that searchers can obtain the highest recall and precision when searching documents according to different needs.
Baidu encyclopedia-the external characteristics of literature
Baidu Encyclopedia —— Literature Retrieval Language