Update Julian Date calculation to return fractions (floats) instead o…

…f an integer.
islamic-network · Sep 21, 2022 · 95ef03d · 95ef03d
1 parent 1e0b5bb
commit 95ef03d
Showing 1 changed file with 27 additions and 3 deletions.
diff --git a/src/PrayerTimes/PrayerTimes.php b/src/PrayerTimes/PrayerTimes.php
@@ -11,6 +11,7 @@
 
 namespace IslamicNetwork\PrayerTimes;
 
+use AlAdhanApi\Helper\PrayerTimesHelper;
 use DateTime;
 use DateTimezone;
 use IslamicNetwork\MoonSighting\Fajr;
@@ -518,19 +519,42 @@ private function computePrayerTimes($times)
         ];
     }
 
+    /**
+     * An Addendum to the PHP method to return a float with the fraction of the day instead of an int.
+     * See https://www.php.net/manual/en/function.gregoriantojd.php.
+     * @param int $month
+     * @param int $day
+     * @param int $year
+     * @return float
+     */
+    private function gregorianToJulianDate(): float
+    {
+        $julianDate = gregoriantojd($this->date->format('n'), $this->date->format('d'), $this->date->format('y'));
+
+        //correct for half-day offset
+        $dayfrac = date('G') / 24 - .5;
+        if ($dayfrac < 0) $dayfrac += 1;
+
+        //now set the fraction of a day
+        $frac = $dayfrac + (date('i') + date('s') / 60) / 60 / 24;
+
+        return ($julianDate + $frac);
+
+    }
     /**
      * @param $factor
      * @param $time
      * @return mixed
      */
     private function asrTime($factor, $time)
     {
-        $julianDate = GregorianToJD($this->date->format('n'), $this->date->format('d'), $this->date->format('Y'));
+        $julianDate = $this->gregorianToJulianDate();
 
-        $decl = $this->sunPosition($julianDate + $time)->declination;
+        $decl = ($this->sunPosition($julianDate + $time))->declination;
 
         $angle = -DMath::arccot($factor+ DMath::tan(abs($this->latitude- $decl)));
 
+
         return $this->sunAngleTime($angle, $time);
     }
 
@@ -539,7 +563,7 @@ private function asrTime($factor, $time)
      */
     private function sunAngleTime($angle, $time, $direction = null)
     {
-        $julianDate = $this->julianDate($this->date->format('Y'), $this->date->format('n'), $this->date->format('d')) - $this->longitude/ (15* 24);
+        $julianDate = $this->julianDate($this->date->format('Y'), $this->date->format('n'), $this->date->format('d')) - $this->longitude / (15* 24);
         $decl = $this->sunPosition($julianDate + $time)->declination;
         $noon = $this->midDay($time);
         $p1 = -DMath::sin($angle) - DMath::sin($decl) * DMath::sin($this->latitude);