PHP Manual

Runtime Configuration

The behaviour of these functions is affected by settings in php.ini.

**Date/Time Configuration Options**
Name	Default	Changeable	Changelog
date.default_latitude	"31.7667"	PHP_INI_ALL	Available since PHP 5.0.0.
date.default_longitude	"35.2333"	PHP_INI_ALL	Available since PHP 5.0.0.
date.sunrise_zenith	"90.583333"	PHP_INI_ALL	Available since PHP 5.0.0.
date.sunset_zenith	"90.583333"	PHP_INI_ALL	Available since PHP 5.0.0.
date.timezone	""	PHP_INI_ALL	Available since PHP 5.1.0.

For further details and definitions of the PHP_INI_* modes, see the Where a configuration setting may be set.

Here's a short explanation of the configuration directives.

date.default_latitude float: The default latitude.
date.default_longitude float: The default longitude.
date.sunrise_zenith float: The default sunrise zenith.
date.sunset_zenith float: The default sunset zenith.
date.timezone string: Prior to PHP 5.3.0, the default timezone used by all date/time functions if the TZ environment variable isn't set; this is longer the case as of 5.3.0. The precedence order is described in the date_default_timezone_get() page. See List of Supported Timezones for a list of supported timezones.

Note: The first four configuration options are currently only used by date_sunrise() and date_sunset().