.NET 開発環境のテスト

.NET 用の MATLAB^® エンジン API には、C# コード例が付随しています。このコード例は、環境をテストし、エンジン API の使用を習得するのに役立ちます。

コード例を含むフォルダーを開くには、コマンド ウィンドウで次のコマンドを実行します。ここで、matlabroot は MATLAB matlabroot コマンドによって返されるパスです。

fullfile(matlabroot,"extern","examples","engines","dotnet")

フォルダーの内容

• dotnet_engine_examples.sln — Microsoft^® Visual Studio^® プロジェクト ファイル。

• Program.cs — プロジェクト内のすべての例を実行するコンソール アプリケーション。

  MainWindow.xaml.cs — ユーザー入力に基づいて階乗を計算する Windows^® GUI アプリケーション。

• .cs ファイル — C# の例のソース ファイル。

• README — Visual Studio を使用した例のビルドと実行方法について説明するテキスト ファイル。

例の概要

これらの例では、以下の方法が示されます。

• C# から MATLAB 関数を呼び出す。

   BasicExample.cs

  /* Copyright 2022 The MathWorks, Inc. */
  
  /*
   * This file contains basic examples of calling MATLAB functions from C#, including:
   * - Calling MATLAB functions from a MATLABEngine instance.
   * - Invoking MATLAB package functions from a MATLABEngine instance.
   * - Passing C# types as arguments to MATLAB functions.
   * - Converting MATLAB return values to C# types.
   */
  using MathWorks.MATLAB.Types;
  using System;
  
  namespace MathWorks.MATLAB.Engine.ConsoleExamples
  {
      public class BasicExample
      {
          public static void Run(dynamic eng)
          {
              // Call a MATLAB function with a single output
              Console.Write("Calling sqrt(2)... ");
              double sqrt = eng.sqrt(2.0);
              Console.WriteLine(sqrt);
  
  
              // Call a MATLAB package function
              Console.Write("Calling matlab.desktop.commandwindow.size()... ");
              double[] size = eng.matlab.desktop.commandwindow.size();
              Console.WriteLine("[{0}]", string.Join(',', size));
  
  
              // Call a MATLAB function with zero outputs
              Console.Write("Calling disp(\"Hello, MATLAB!\")... ");
              RunOptions opts = new RunOptions() { Nargout = 0 };
              eng.disp(opts, "Hello, MATLAB!");
  
  
              // Call a MATLAB function with two outputs
              Console.Write("Calling weekday(\"10-10-2010\")... ");
              opts = new RunOptions() { Nargout = 2 };
              (double, string) result = eng.weekday(opts, "10-10-2010");
              Console.WriteLine(result);
              
          }
      }
  }

• 例外を処理する。

   ExceptionExample.cs

  /* Copyright 2022 The MathWorks, Inc. */
  
  /*
   * This file contains examples of exception handling, which may be thrown if:
   * - The application cannot find or connect to MATLAB.
   * - A error occurs when executing a MATLAB function.
   * - An unsupported .NET type is used as an argument to a MATLAB function.
   * - A MATLAB type cannot be converted to a particular .NET type.
   */ 
  using MathWorks.MATLAB.Exceptions;
  using MathWorks.MATLAB.Types;
  using System;
  
  namespace MathWorks.MATLAB.Engine.ConsoleExamples
  {
      public class ExceptionExample
      {
          public static void Run(dynamic eng)
          {
              // If MATLAB is not available, a MATLABNotAvailableException will be thrown.
              const string nameThatDoesNotExist = "unknown_matlab";
              Console.Write("Connecting to MATLAB {0}... ", nameThatDoesNotExist);
              try
              {
                  eng = MATLABEngine.ConnectMATLAB(nameThatDoesNotExist);
              }
              catch (MATLABNotAvailableException)
              {
                  Console.WriteLine("MATLAB {0} does not exist.", nameThatDoesNotExist);
              }
  
  
              // If a runtime error occurs, a MATLABExecutionException will be thrown. 
              // The error text is forwarded to Console.Error by default. 
              // This behavior may be modified with the Error property of a RunOptions instance.
              Console.Write("Calling MATLAB function unknown_function... ");
              try
              {
                  eng.unknown_function();
              }
              catch (MATLABExecutionException) { }
  
  
              // If a .NET type cannot be converted to a MATLAB type,
              // an UnsupportedTypeException will be thrown.
              Console.Write("Sending a System.Decimal to MATLAB... ");
              try
              {
                  decimal someUnsupportedData = decimal.One;
                  eng.disp(new RunOptions() { Nargout = 0 }, someUnsupportedData);
              }
              catch (UnsupportedTypeException e)
              {
                  Console.WriteLine(e.Message);
              }
  
  
              // If a MATLAB type cannot be converted to a .NET type,
              // a System.InvalidCastException will be thrown.
              Console.Write("Converting a MATLAB char array to System.Double... ");
              try
              {
                  double notADouble = eng.eval(" 'this is a char array' ");
              }
              catch (InvalidCastException e)
              {
                  Console.WriteLine(e.Message);
              }
          }
      }
  }

• C# アプリケーションから MATLAB オブジェクトを操作する。

   ObjectExample.cs

  /* Copyright 2022 The MathWorks, Inc. */
  
  /*
   * This file contains examples of how to interact with MATLAB objects from
   * a C# application using the `dynamic` keyword. Examples include:
   * - Calling a MATLAB class constructor.
   * - Accessing properties on a MATLAB class.
   * - Invoking methods on a MATLAB class.
   */
  using MathWorks.MATLAB.Types;
  using System;
  
  namespace MathWorks.MATLAB.Engine.ConsoleExamples
  {
      public class ObjectExample
      {
          public static void Run(dynamic eng)
          {
              // Change the directory so our class is visible to MATLAB
              Console.Write("Changing working folder... ");
              string oldDir = eng.pwd();
              string newDir = eng.fullfile(eng.matlabroot(), "extern", "examples", "engines", "dotnet", "console");
              RunOptions opts = new RunOptions() { Nargout = 0 };
              eng.cd(opts, newDir);
              Console.WriteLine("Changed to {0}", newDir);
  
  
              // Create a Triangle and assign it to the `dynamic` type
              Console.Write("Creating a Triangle... ");
              double edgeLength = 1;
              dynamic triangle = eng.Triangle(edgeLength, edgeLength);
              Console.WriteLine("Created a 1x1 Triangle.");
  
  
              // Access properties of Triangle
              Console.Write("Changing triangle.Base to 3 and triangle.Height to 4... ");
              triangle.Base = 3.0;
              triangle.Height = 4.0;
              double area = triangle.Area;
              Console.WriteLine("triangle.Area is now {0}", area);
  
  
              // Call methods of Triangle
              Console.Write("Resizing triangle by 10... ");
              opts = new RunOptions() { Nargout = 0 };
              triangle.resize(opts, 10.0);
              area = triangle.Area;
              Console.WriteLine("triangle.Area is now {0}", area);
  
              Console.WriteLine("Displaying triangle...");
              triangle.disp(opts);
  
  
              // Restore the original working directory
              Console.Write("Restoring original working folder... ");
              opts = new RunOptions() { Nargout = 0 };
              eng.cd(opts, oldDir);
              Console.WriteLine("Changed to {0}", oldDir);
          }
      }
  }

• C# アプリケーションから MATLAB 構造体を操作する。

   StructExample.cs

  /* Copyright 2022 The MathWorks, Inc. */
  
  /*
   * This file contains examples of how to interact with MATLAB structs from
   * a C# application using the `dynamic` keyword and the MATLABStruct data type. 
   *  Examples include:
   * - Creating a MATLABStruct
   * - Calling methods of a MATLABStruct
   * - Passing a MATLABStruct to MATLAB
   */
  using MathWorks.MATLAB.Types;
  using System;
  using System.Collections.Generic;
  
  namespace MathWorks.MATLAB.Engine.ConsoleExamples
  {
      public class StructExample
      {
          public static void Run(dynamic eng)
          {
  
              // Create a MATLABStruct and assign it to the 'dynamic' type
              Console.WriteLine("Creating a MATLABStruct... ");
              MATLABStruct mStruct = new MATLABStruct(("a", 1), ("b", 2));
              dynamic dynamicMStruct = mStruct;
              Console.WriteLine("Created a 1x1 MATLABStruct with 2 fields");
  
  
              // Access fields of a MATLABStruct
              Console.WriteLine("Display values of fields... ");
              double a = mStruct.GetField("a");
              double b = dynamicMStruct.b;
              Console.WriteLine("(a, b): ( {0} , {1})",a, b);
  
  
              // Call methods of MATLABStruct
              Console.WriteLine("Calling methods of MATLABStruct... ");
              int numFields = mStruct.Count();
              bool containsFieldA = mStruct.IsField("a");
              IEnumerable<string> fieldNames = mStruct.GetFieldNames();
              Console.WriteLine("The struct contains {0} fields", numFields);
  
              // Call MATLAB function with a MATLABStruct as input
              eng.disp(new RunOptions(nargout: 0), mStruct);
              
          }
      }
  }

• MATLAB ベース ワークスペースを操作する。

   WorkspaceExample.cs

  /* Copyright 2022 The MathWorks, Inc. */
  
  /*
   * This file contains examples for interacting with the MATLAB base workspace, including:
   * - Setting variables in the MATLAB base workspace.
   * - Retrieving variables from the MATLAB base workspace.
   * - Querying the MATLAB base workspace for the existence of variables.
   */
  using MathWorks.MATLAB.Types;
  using System;
  using System.Linq;
  
  namespace MathWorks.MATLAB.Engine.ConsoleExamples
  {
      public class WorkspaceExample
      {
          public static void Run(dynamic eng)
          {
              // Set workspace variables using the MATLABWorkspace dictionary
              Console.Write("Setting workspace variables... ");
              MATLABWorkspace workspace = eng.Workspace;
              workspace["x"] = 3.14;
  
  
              // Set workspace variables using the 'eval' function
              RunOptions opts = new RunOptions() { Nargout = 0 };
              eng.eval(opts, "y = 'this is a char array';");
  
  
              // Display information on the MALTAB base workspace
              int numVars = workspace.Count;
              Console.WriteLine("There are {0} variables in the MATLAB base workspace.", numVars);
  
              string[] varNames = workspace.Keys.ToArray();
              Console.WriteLine("  It contains these variables: {0}", string.Join(", ", varNames));
  
  
              // Get workspace variables using the MATLABWorkspace dictionary
              Console.WriteLine("Retrieving workspace variables... ");
              double valueOfX = workspace["x"];
              string valueOfY = workspace["y"];
              Console.WriteLine("  x == {0}", valueOfX);
              Console.WriteLine("  y == \"{0}\"", valueOfY);
  
  
              // Query for the existence of particular variables
              Console.Write("Querying the value of x... ");
              if (workspace.TryGetValue("x", out valueOfX))
                  Console.WriteLine("x == {0}", valueOfX);
              else
                  Console.WriteLine("x does not exist in the workspace.");
  
              Console.Write("Querying the value of z... ");
              if (workspace.TryGetValue("z", out string valueOfZ))
                  Console.WriteLine("z == {0}", valueOfZ);
              else
                  Console.WriteLine("z does not exist in the workspace.");
          }
      }
  }

例のビルドと実行

例をビルドして実行するには、コマンド ウィンドウで次のコマンドを実行して、例のファイルをパス上の書き込み可能なフォルダーにコピーします。

copyfile(fullfile(matlabroot,"extern","examples","engines","dotnet","dotnet_engine_examples.sln"),".","f")
copyfile(fullfile(matlabroot,"extern","examples","engines","dotnet","console\*.*"),".\console\","f")

Windows プラットフォームでは、次のコマンドを実行して Windows GUI アプリケーションをコピーします。

copyfile(fullfile(matlabroot,"extern","examples","engines","dotnet","gui\*.*"),".\gui\","f")

README ファイルに記載されている次の指示に従います。

Copyright 2023 The MathWorks, Inc.

These instructions are for compiling and running a C# application
that uses MATLAB Engine API for .NET from the command line.

Projects can also be opened in your favorite IDE.

In these instructions, replace <matlabroot> with the value returned 
by the matlabroot function in MATLAB.


## PREREQUISITES ##

1. Install the latest .NET SDK from https://dotnet.microsoft.com/download
   The full .NET SDK is required, not just the .NET Runtime.

2. Set up environment variables to point to your MATLAB installation.
   Use these environment variable names and paths:

Windows:
  PATH
  <matlabroot>\extern\bin\win64

Apple Silicon:
  DYLD_LIBRARY_PATH
  <matlabroot>/extern/bin/maca64

Linux:
  LD_LIBRARY_PATH
  <matlabroot>/extern/bin/glnxa64:<matlabroot>/sys/os/glnxa64
  
3. Copy the example files to a working directory for example "C:\work".  
   The files that need to be copied are as follows:

Windows:
   dotnet_engine_examples.sln
   all files in the console and gui directories
   
Apple macOS and Linux:
   dotnet_engine_examples.sln
   all files in the console directory

## COMPILING ##

Use the 'dotnet build' command to compile all example projects.
  $> cd C:\work
  $> dotnet build /p:matlabroot=<matlabroot>


## RUNNING ##

Use the 'dotnet run' command to execute a particular example project.
To run the console example:
  $> dotnet run --no-build --project console
  
  
To run the gui example (Windows only):
  $> dotnet run --no-build --project gui

参考

トピック

• .NET エンジン プログラムのビルド要件