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Problems with MATLAB Engine API for Java

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Manuel Rios
Manuel Rios on 18 Feb 2017
Answered: Bo Li on 15 Mar 2017
I am trying to compile this piece of code:
import com.mathworks.engine.*;
public class javaEvalFunc {
public static void main(String[] args) throws Exception {
MatlabEngine eng = MatlabEngine.startMatlab();
eng.evalAsync("[X, Y] = meshgrid(-2:0.2:2);");
eng.evalAsync("Z = X .* exp(-X.^2 - Y.^2);");
Object[] Z = eng.getVariable("Z");
eng.close();
}
}
I found it on this web page: Java Engine
As you can see I need a reference to com.mathworks.engine.*;
This Page Info says that the .jar file that I need to Add is in this Path:
matlabroot/extern/engines/java/jar/engine.jar
But in my computer I just have a folder called phyton in this path
matlabroot/extern/engines
Where can I find the .jar file that I need ?
I am using Eclipse IDE by the way. thanks.
  3 Comments
Anushan Vasantharajah
Anushan Vasantharajah on 2 Mar 2017
I also have the same problem. Any one know the answer? :( please guys give some idea to sole the problem.

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Accepted Answer

Guillaume
Guillaume on 2 Mar 2017
It would help if you used the documentation that come with your version. In R2016a, you will find no mention of the java engine, and that's because it's been introduced in R2016 (See the release notes under advanced software development).
You will have to upgrade to R2016b.

More Answers (1)

Bo Li
Bo Li on 15 Mar 2017
With a simple test "example.java" like this:
import com.mathworks.engine.*;
public class CNN
{
public static void main(String[] args) throws Exception{
MatlabEngine eng = MatlabEngine.startMatlab();
double[] a = {2.0 ,4.0, 6.0};
double[] roots = eng.feval("sqrt", a);
eng.close();
}
}
Following commands work for me:
C:\JavaEngine\src>javac -classpath <matlabroot>\\extern\\engines\\java\\jar\\engine.jar
example.java
C:\JavaEngine\src>set PATH=<matlabroot>\\bin\\win64;%PATH%
C:\JavaEngine\src>java -classpath .;<matlabroot>\\extern\\engines\\java\\jar\\engine.jar
example

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