can't calculate ln(e)

[Antonyo Jaydenx]

public static void main(String[] args) {

        JEP j= new JEP();

        j.addStandardConstants();

        j.addComplex();

        j.addVariable("x", 1); // 1 va  a ser el valor de la expresion x

        j.parseExpression("x^2-2*ln(e)"); // el valor sera pasado por esta ecuacion

        

        System.out.println(j.getValue());

        

        

    }

it only say me "Nan"

[Richard Morris]

You need to add in the set of functions. 

        j.addStandardFunctions();

currently its treating 'ln' as an undeclared variable, so the expression is 'x^2-2*ln * e'.