Method unbiased_stdev

libraries/Statistic/Statistic.h:215–219

  value_type unbiased_stdev() const {
    if (!_useStdDev) return NaN;
    if (_cnt < 2) return NaN; // prevent DIV0 error
    return std::sqrt( _extra.ssqdif() / (_cnt - 1));
  }


  // deprecated methods: