public function toMJD($scale = null)
    {
        $mjd = static::MJD;

        if ($scale) {
            return bcsub(bcadd($this->jd, $this->dayFrac, $scale), $mjd,
              $scale);
        } else {
            return $this->jd + $this->dayFrac - $mjd;
        }
    }
public function toMJD($scale = null)
    {
        $mjd = static::MJD;

        if ($scale) {
            return bcsub(bcadd($this->jd, $this->dayFrac, $scale), $mjd,
              $scale);
        } else {
            return $this->jd + $this->dayFrac - $mjd;
        }
    }
public function toMJD ( $ scale = null ) { $ mjd = static :: MJD ; if ( $ scale ) { return bcsub ( bcadd ( $ this -> jd , $ this -> dayFrac , $ scale ) , $ mjd , $ scale ) ; } else { return $ this -> jd + $ this -> dayFrac - $ mjd ; } }
Returns a Modified Julian date representation of this instance.

@param  int $scale Optional additional decimal precision

@return float|string
Returns a Modified Julian date representation of this instance .