package org.matheclipse.core.builtin.constant;

import org.matheclipse.core.eval.interfaces.AbstractSymbolEvaluator;
import org.matheclipse.core.eval.interfaces.ISignedNumberConstant;
import org.matheclipse.core.expression.F;
import org.matheclipse.core.interfaces.IExpr;
import org.matheclipse.core.interfaces.ISymbol;

/**
 * Euler gamma constant
 * 
 * See Euler–Mascheroni constant
 */
public class EulerGamma extends AbstractSymbolEvaluator implements
		ISignedNumberConstant {
	final static public double EULER_GAMMA = 0.57721566490153286060651209008240243104215933593992;
	
	public EulerGamma() {
	}

	@Override
	public void setUp(final ISymbol symbol) {
		symbol.setAttributes(ISymbol.CONSTANT);
	}

	@Override
	public IExpr numericEval(final ISymbol symbol) {
		return F.num(EULER_GAMMA);
	}

	public double evalReal() {
		return EULER_GAMMA;
	}

}