Rationalize.java :  » Algebra » symja » org » matheclipse » core » reflection » system » Java Open Source

package org.matheclipse.core.reflection.system;

import org.matheclipse.basic.Config;
import org.matheclipse.core.eval.EvalEngine;
import org.matheclipse.core.eval.exception.Validate;
import org.matheclipse.core.eval.interfaces.AbstractFunctionEvaluator;
import org.matheclipse.core.expression.F;
import org.matheclipse.core.interfaces.IAST;
import org.matheclipse.core.interfaces.IComplexNum;
import org.matheclipse.core.interfaces.IExpr;
import org.matheclipse.core.interfaces.IInteger;
import org.matheclipse.core.interfaces.INum;
import org.matheclipse.core.interfaces.IRational;
import org.matheclipse.core.interfaces.ISymbol;

public class Rationalize extends AbstractFunctionEvaluator {

  public Rationalize() {
  }

  @Override
  public IExpr evaluate(final IAST ast) {
    Validate.checkSize(ast, 2);
    IExpr arg1 = ast.get(1);
    try {
      // try to convert into a fractional number
      final EvalEngine engine = EvalEngine.get();
      arg1 = engine.evaluate(arg1);
      if (arg1 instanceof IInteger || arg1 instanceof IRational) {
        return arg1;
      }
      if (arg1 instanceof INum) {
        return F.fraction(((INum) arg1).getRealPart());
      }
      if (arg1 instanceof IComplexNum) {
        return F.complex(((IComplexNum) arg1).getRealPart(), ((IComplexNum) arg1).getImaginaryPart());
      }
    } catch (Exception e) {
      if (Config.SHOW_STACKTRACE) {
        e.printStackTrace();
      }
    }

    return null;
  }

  public void setUp(final ISymbol symbol) {
    symbol.setAttributes(ISymbol.HOLDALL|ISymbol.LISTABLE);
  }
}