date_sunset

(PHP 5, PHP 7, PHP 8)

date_sunset — Returns time of sunset for a given day and location

Avviso

This function has been DEPRECATED as of PHP 8.1.0. Relying on this function is highly discouraged. Use date_sun_info() instead.

Descrizione

date_sunset(
    int $timestamp,
    int $returnFormat = SUNFUNCS_RET_STRING,
    ?float $latitude = null,
    ?float $longitude = null,
    ?float $zenith = null,
    ?float $utcOffset = null
): string|int|float|false

date_sunset() returns the sunset time for a given day (specified as a timestamp) and location.

Elenco dei parametri

timestamp

The timestamp of the day from which the sunset time is taken.

returnFormat

**`returnFormat` constants**
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 int (timestamp)	1095034606

latitude

Defaults to North, pass in a negative value for South. See also: date.default_latitude

longitude

Defaults to East, pass in a negative value for West. See also: date.default_longitude

zenith

zenith is the angle between the center of the sun and a line perpendicular to earth's surface. It defaults to date.sunset_zenith

**Common `zenith` angles**
Angle	Description
90°50'	Sunset: the point where the sun becomes invisible.
96°	Civil twilight: conventionally used to signify the end of dusk.
102°	Nautical twilight: the point at which the horizon ends being visible at sea.
108°	Astronomical twilight: the point at which the sun ends being the source of any illumination.

utcOffset

Specified in hours. The utcOffset is ignored, if returnFormat is SUNFUNCS_RET_TIMESTAMP.

Valori restituiti

Returns the sunset time in a specified returnFormat on success o false in caso di fallimento. One potential reason for failure is that the sun does not set at all, which happens inside the polar circles for part of the year.

Errori/Eccezioni

Ogni chiamata a una funzione data/ora genera un E_NOTICE se il time zone non è valido, e/o un messaggio E_STRICT o E_WARNING se si usano le impostazioni di sistema o la variabile d'ambiente TZ. Vedere anche date_default_timezone_set()

Log delle modifiche

Versione	Descrizione
8.1.0	This function has been deprecated in favor of date_sun_info().
8.0.0	`latitude`, `longitude`, `zenith` and `utcOffset` are nullable now.

Esempi

Example #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);

?>

Il precedente esempio visualizzerà qualcosa simile a:

Mon Dec 20 2004, sunset time : 18:13

Example #2 No sunset

<?php
$solstice = strtotime('2017-12-21');
var_dump(date_sunset($solstice, SUNFUNCS_RET_STRING, 69.245833, -53.537222));
?>

Il precedente esempio visualizzerà:

bool(false)

Vedere anche:

date_sun_info() - Returns an array with information about sunset/sunrise and twilight begin/end

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User Contributed Notes 3 notes

down

matt at mctsoft dot net ¶

5 years ago


yes SUNFUNCS_RET_TIMESTAMP does return GMT(0) time

so something like...

$arr = localtime(date_sunset(time(),SUNFUNCS_RET_TIMESTAMP,51.5,0)); // London

$hh = $arr[2];
$mm = $arr[1];

Will give figure out your localtime and daylight saving (BST)

down

-1

nospam at nomail dot com ¶

6 years ago


maybe I am wrong, but I think

SUNFUNCS_RET_TIMESTAMP     return GMT(0) time

SUNFUNCS_RET_STRING     Return local time
SUNFUNCS_RET_DOUBLE     Return local time

down

-25

michael at dayah dot com ¶

18 years ago


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";

}

?>

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