主要内容

进出口MATLAB物体使用MongoDB

此示例显示如何从MATLAB导出对象®工作区进入MongoDB.®using the Database Toolbox™ interface for MongoDB. The export serializes the objects in MongoDB. Then, the example shows how to import objects back into the MATLAB workspace. The import deserializes the objects and recreates them in MATLAB for method execution. After the export and import, the example shows how to drop the collection.

To run this example, you must first install the Database Toolbox interface for MongoDB. For details, seeDatabase Toolbox Interface for MongoDB Installation.

In this example, the objects belong to theTensileData班级。此类是Matlab中的示例类。用于创建对象的数据是示例数据。有关详细信息，请参阅表示具有类的结构化数据. To run the code in this example, define the class in the current folder.

The data represents tensile stress or strain measurements. To calculate the elastic modulus of various materials, use this data. In simple terms, stress is the force applied to a material, and strain is the resulting deformation. The ratio of stress to strain defines a characteristic of the material.

Create Objects

Create theTensileDataobjectstdcsfor carbon steel materials andtdssfor stainless steel materials.

tdcs = TensileData('carbon steel',1,...[2E4 4E4 6E4 8E4]，[。12 .20 .31 .40]）;TDSS = Tensiledata（'stainless steel',1,...[2e4 4e4 6e4 8e4],[.06 .10 .16 .20]);

Connect toMongoDB

Create a MongoDB connection to the databasemongotest. Here, the database serverdbtb01hosts this database using port number27017.

server ="dbtb01"; port = 27017; dbname ="mongotest"; conn = mongo(server,port,dbname)
conn = mongo with properties: Database: 'mongotest' UserName: '' Server: {'dbtb01'} Port: 27017 CollectionNames: {'airlinesmall', 'employee', 'largedata' ... and 3 more} TotalDocuments: 23485919

conn是个mongoobject that contains the MongoDB connection. The object properties contain information about the connection and the database.

  • The database name ismongotest.

  • The user name is blank.

  • The database server isdbtb01.

  • The port number is27017.

  • This database contains six document collections. The first three collection names areairlinesmall,员工， 和largedata.

  • 该数据库包含23,485,919件文件。

Verify the MongoDB connection.

Isopen（Conn）
ans = logical 1

数据库连接成功，因为开了function returns1. Otherwise, the database connection is closed.

Create Collection inMongoDB

Create theTensileDatacollection using the MongoDB connection.

collection ="TensileData"; createCollection(conn,collection)

Export Objects intoMongoDB

Export theTensileDataobjects into the collection. The插入function serializes theTensileDataobjects into a JSON-style structure.ntdcs和ntdss包含导出到集合中的对象数。

ntdcs = insert(conn,collection,tdcs); ntdss = insert(conn,collection,tdss);

Import Objects intoMATLAB工作区

Import theTensileDataobjects into the MATLAB workspace. The找function deserializes theTensileDataobjects into thedocumentsstructure array.

documents = find(conn,collection);

Recreate the objects in the MATLAB workspace.

tdcs = TensileData(documents(1).Material,documents(1).SampleNumber,...documents(1).Stress,documents(1).Strain); tdss = TensileData(documents(2).Material,documents(2).SampleNumber,...documents(2).Stress,documents(2).Strain);

您可以在Matlab工作区中出现后执行对象的方法。

Remove Documents and Drop Collection

Remove all documents from the collection.n包含从集合中删除的文档数。

n =删除（Conn，Collection，'{}')
n = 2

放下收藏。

dropCollection(康涅狄格州、收集)

CloseMongoDBConnection

close(conn)

See Also

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External Websites

Database Toolbox Documentation

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