Diese Seite bei php.net
The PHP manual text and comments are covered by the Creative Commons Attribution 3.0 License © the PHP Documentation Group - Impressum - mail("TO:Reinhard Neidl",...)
(PHP 5)
date_sunset — Returns time of sunset for a given day and location
date_sunset() returns the sunset time for a given day (specified as a timestamp) and location.
The timestamp of the day from which the sunset time is taken.
| constant | description | example |
|---|---|---|
| SUNFUNCS_RET_STRING | returns the result as string | 16:46 |
| SUNFUNCS_RET_DOUBLE | returns the result as float | 16.78243132 |
| SUNFUNCS_RET_TIMESTAMP | returns the result as integer (timestamp) | 1095034606 |
Defaults to North, pass in a negative value for South. See also: date.default_latitude
Defaults to East, pass in a negative value for West. See also: date.default_longitude
Default: date.sunset_zenith
Specified in hours.
Jeder Aufruf der Datums- und Zeitfunktionen generiert eine E_NOTICE-Warnung, wenn die Zeitzone ungültig ist und eine E_STRICT-Nachricht oder eine E_WARNING-Warnung, wenn die Systemeinstellung oder die TZ-Umgebungsvariable genutzt wird. Siehe auch date_default_timezone_set()
| Version | Beschreibung |
|---|---|
| 5.1.0 | Erzeugt nun E_STRICT- und E_NOTICE-Zeitzonenfehler. |
Returns the sunset time in a specified format on successIm Fehlerfall wird FALSE zurückgegeben..
Beispiel #1 date_sunset() example
<?php
/* calculate the sunset time for Lisbon, Portugal
Latitude: 38.4 North
Longitude: 9 West
Zenith ~= 90
offset: +1 GMT
*/
echo date("D M d Y"). ', sunset time : ' .date_sunset(time(), SUNFUNCS_RET_STRING, 38.4, -9, 90, 1);
?>
Das oben gezeigte Beispiel erzeugt eine ähnliche Ausgabe wie:
Mon Dec 20 2004, sunset time : 18:13
I use an IP to location database to determine the visitor's approximate latitude and longitude and then serve them a day or night color scheme based on whether it is before civil dawn or dusk. I've had problems when not specifying the timezone, specifically a 1 hour error, so I use GMT.
<?php
date_default_timezone_set("GMT");
function scheme() {
$sunrise = date_sunrise(time(), SUNFUNCS_RET_DOUBLE, $latitude, $longitude, 96, 0);
$sunset = date_sunset(time(), SUNFUNCS_RET_DOUBLE, $latitude, $longitude, 96, 0);
$now = date("H") + date("i") / 60 + date("s") / 3600;
if ($sunrise < $sunset)
if (($now > $sunrise) && ($now < $sunset)) return "day";
else return "night";
else
if (($now > $sunrise) || ($now < $sunset)) return "day";
else return "night";
}
?>
A way to use this:
<?php
// De Bilt, The Netherlands, weather station #06260
$lat = 52.10; // North
$long = 5.18; // East
$offset = 1; // difference between GMT and local time in hours
$zenith=90+50/60;
echo "<br><p>Sunrise: ".date_sunrise(time(), SUNFUNCS_RET_STRING, $lat, $long, $zenith, $offset);
echo "<br>Sunset: ".date_sunset(time(), SUNFUNCS_RET_STRING, $lat, $long, $zenith, $offset);
$zenith=96;
echo "<br><p>\"Civilian Twilight\" start: ".date_sunrise(time(), SUNFUNCS_RET_STRING, $lat, $long, $zenith, $offset);
echo "<br>\"Civilian Twilight\" end: ".date_sunset(time(), SUNFUNCS_RET_STRING, $lat, $long, $zenith, $offset);
$zenith=102;
echo "<br><p>\"Nautical Twilight\" start: ".date_sunrise(time(), SUNFUNCS_RET_STRING, $lat, $long, $zenith, $offset);
echo "<br>\"Nautical Twilight\" end: ".date_sunset(time(), SUNFUNCS_RET_STRING, $lat, $long, $zenith, $offset);
$zenith=108;
echo "<br><p>\"Astronomical Twilight\" start: ".date_sunrise(time(), SUNFUNCS_RET_STRING, $lat, $long, $zenith, $offset);
echo "<br>\"Astronomical Twilight\" end: ".date_sunset(time(), SUNFUNCS_RET_STRING, $lat, $long, $zenith, $offset);
?>
Thanks to George King.
More sources about this topic:
http://www.qarlos.free.fr/navegacion/Sextante/formulas.htm
http://williams.best.vwh.net/sunrise_sunset_algorithm.htm
http://www.kevinboone.com/suntimes.html
http://star-www.st-and.ac.uk/~fv/webnotes/chapt12.htm
Diese Seite bei php.net