/* (non-Javadoc) * @see fr.expression4j.core.Expression#evaluate(fr.expression4j.core.Parameters) */ public MathematicalElement evaluate(OperatorManager operatorManager, Parameters parameters) throws EvalException { try { MathematicalElement x = parameters.getParameter("x"); return NumberFactory.createReal( new BigDecimal(Math.atan(x.getRealValue(mc).doubleValue()), mc)); } catch (ParametersException pe) { throw new EvalException("Could not find parameter x for function " + getName()); } }