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
(PHP 5)
date_sunrise — Returns time of sunrise for a given day and location
$timestamp
[, int $format
= SUNFUNCS_RET_STRING
[, float $latitude
= ini_get("date.default_latitude")
[, float $longitude
= ini_get("date.default_longitude")
[, float $zenith
= ini_get("date.sunrise_zenith")
[, float $gmt_offset
= 0
]]]]] )
date_sunrise() returns the sunrise time for a given
day (specified as a timestamp
) and location.
timestamp
The timestamp
of the day from which the sunrise
time is taken.
format
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 |
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
Default: date.sunrise_zenith
gmtoffset
Specified in hours.
Returns the sunrise time in a specified format
on
success 或者在失敗時回傳 FALSE
.
如果時區無效,每個對日期/時間函式的呼叫都會產生一個
E_NOTICE
訊息,如果使用系統設定或 TZ
環境變數則會產生 E_STRICT
消息。參見
date_default_timezone_set()
版本 | 說明 |
---|---|
5.1.0 | 現在發出
|
Example #1 date_sunrise() example
<?php
/* calculate the sunrise time for Lisbon, Portugal
Latitude: 38.4 North
Longitude: 9 West
Zenith ~= 90
offset: +1 GMT
*/
echo date("D M d Y"). ', sunrise time : ' .date_sunrise(time(), SUNFUNCS_RET_STRING, 38.4, -9, 90, 1);
?>
上例的輸出類似於:
Mon Dec 20 2004, sunrise time : 08:54
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
If you are working in multiple timezones getting the offset from a date is a little tricky because you need it in hours.
<?php
$time = new DateTime('now', new DateTimeZone('America/Los_Angeles'));
date_sunrise(
$time->getTimestamp(),
SUNFUNCS_RET_TIMESTAMP,
38.4,
-9,
90,
$time->getOffset() / 3600
);
After some searching, I finally found a website that can calculate the sun's zenith. Just look up your city's lat/long (remember, west/south are negative even if it doesn't show where you look up the lat/long) and the time of sunrise/sunset and use this site:
http://solardat.uoregon.edu/cgi-bin/SolarPositionCalculator.cgi
You have to enter in the sunrise/sunset times separately, but it works.
San Diego is:
Lat: 32.73
Long: -117.17
Sunrise Z.: 90.7379
Sunset Z.: 90.8880