extPV function

dynamic extPV(
  1. dynamic v1,
  2. dynamic v2,
  3. dynamic v3
)

PV(rate, nper, pmt): present value

Implementation

dynamic extPV(dynamic v1, dynamic v2, dynamic v3) {
  final rate = varToDouble(v1);
  final nper = varToInt(v2);
  final pmt = varToDouble(v3);
  if (rate == 0) return -pmt * nper;
  return -pmt / rate * (1 - pow(1 + rate, -nper));
}