How to call method associated with button in js

Hello;

I have method in .js file and this method is associated with button (it will be run when clicking on the button).
Can I use this method within the script from another method? How to call it?
I tried to call it using payments_calculate (frm); but nothing happened.

    payments_calculate: function(frm) {
            cur_frm.set_value("total_paid_amount", flt(cur_frm.doc.q1_amount) + flt(cur_frm.doc.q2_amount) + flt(cur_frm.doc.q3_amount) + flt(cur_frm.doc.q4_amount));
            cur_frm.set_value("total_paid_value", flt(cur_frm.doc.total_paid_amount));
            var net_payment;
            net_payment = flt(cur_frm.doc.total_paid_amount) - flt(cur_frm.doc.total_payable_tax) + flt(cur_frm.doc.balance);
            if (net_payment < 0) {
                    net_payment = 0 - net_payment;
                    cur_frm.set_value("balance_to_be_paid", net_payment);
                    cur_frm.set_value("balance_to_be_returned", 0);
            }
            else if (net_payment > 0) {
                    cur_frm.set_value("balance_to_be_returned", net_payment);
                    cur_frm.set_value("balance_to_be_paid", 0);
            }
            else {
                    cur_frm.set_value("balance_to_be_paid", net_payment);
                    cur_frm.set_value("balance_to_be_returned", net_payment);
            }
    }

Regards
Bilal