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androidnoclassdeffounderrorjscience

java.lang.NoClassDefFoundError: org.jscience.mathematics.function.Variable$Local

I have sample code downloaded from here for using jscience.

But when I use it, it gives this message:

E/AndroidRuntime(1296): java.lang.NoClassDefFoundError:org.jscience.mathematics.function.Variable$Local

Am I missing something? Of course I imported the jscience jar lib to my project. But still can't figure this out.

    Variable.Local<Rational> varX = new Variable.Local<Rational>("x");
    Variable.Local<Rational> varY = new Variable.Local<Rational>("y");

    // f(x, y) =  x² + x·y + 1;
    Polynomial<Rational> x = Polynomial.valueOf(Rational.ONE, varX);
    Polynomial<Rational> y = Polynomial.valueOf(Rational.ONE, varY);
    Polynomial<Rational> fx_y = x.pow(2).plus(x.times(y)).plus(Rational.ONE);
    System.out.println("f(x,y) = " + fx_y);

    // Evaluates f(1,0) 
    System.out.println("f(1,0) = " + fx_y.evaluate(Rational.ONE, Rational.ZERO));

    // Calculates df(x,y)/dx
    System.out.println("df(x,y)/dx = " + fx_y.differentiate(varX));
Solution

  • The class org.jscience.mathematics.function.Variable$Local is definitely in the JAR:

    $ jar tf JScience/lib/jscience.jar | grep Variable\$Local
org/jscience/mathematics/function/Variable$Local.class

    Verify that the required libraries are listed in the Class-Path attribute in your JAR's manifest; use a tool like the one cited here to be sure:

    Class-Path: lib/jscience.jar lib/javolution.jar …

    Addendum: As noted in a comment by @max, the ADT 17 library directory should be named libs.