SymbolicEngine.java

package org.eclipse.iee.pad.formula;

import java.io.StringWriter;

import org.apache.log4j.Logger;
import org.matheclipse.core.eval.EvalEngine;
import org.matheclipse.core.eval.EvalUtilities;
import org.matheclipse.core.eval.TeXUtilities;
import org.matheclipse.core.expression.F;
import org.matheclipse.core.form.output.OutputFormFactory;
import org.matheclipse.core.form.output.StringBufferWriter;
import org.matheclipse.core.interfaces.IExpr;
import org.osgi.service.component.annotations.Component;

@Component(service = SymbolicEngine.class)
public class SymbolicEngine {

	private final EvalUtilities fUtil;

	private static final Logger logger = Logger.getLogger(SymbolicEngine.class);

	public SymbolicEngine() {
		F.initSymbols(null);
		fUtil = new EvalUtilities();
	}
	
	public static boolean validate(String text) {

		try {

			if (getTeX(text) == "") {
				return false;
			} else {
				return true;
			}
		} catch (Exception e) {
			return false;
		}
	}


	public String getOutput(String expression) {
		String output = "";

		IExpr result = null;
		StringBufferWriter buf = new StringBufferWriter();

		logger.debug("expression: " + expression);
		
		try {
			result = fUtil.evaluate(expression);

			OutputFormFactory.get().convert(buf, result);

			output = buf.toString();

			logger.debug("result: " + output);

		} catch (Exception e) {
			e.printStackTrace();
			return "";
		}

		return output.replaceAll("->", "=");
	}

	public static String getTeX(String expression) {
		/* Convert to TeX */
		EvalEngine engine = new EvalEngine();
		TeXUtilities texUtil = new TeXUtilities(engine);

		StringWriter stw = new StringWriter();
		texUtil.toTeX(expression, stw);
		String output = stw.toString();

		return output;
	}

}