private void getResult() {
        
        DecimalFormat df = new DecimalFormat("0", DecimalFormatSymbols.getInstance(Locale.ENGLISH));
        df.setMaximumFractionDigits(340);
        
        String s = this.expression.getText();
        
        if(!this.answer.getText().isEmpty()) {
            s = s.replace("Ans", this.answer.getText());
        } else {
            s = s.replace("Ans", "0");
        }
        
        s = s.replace("Pi", Double.toString(Math.PI));
        
        String r = this.calculate(s);
        
        if(!this.error) {
            this.answer.setText(df.format(Double.parseDouble(r)));
        } else {
            this.answer.setText(r);
        }
        
        this.eraseExpression = true;
    }