## 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 |
date.default_longitude | "35.2333" | PHP_INI_ALL |
date.sunrise_zenith | "90.583333" | PHP_INI_ALL |
date.sunset_zenith | "90.583333" | PHP_INI_ALL |
date.timezone | "" | PHP_INI_ALL | Available as of 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

  The default timezone used by all date/time functions. Prior to PHP 5.4.0, this would only work if the TZ environment variable was not set. The precedence order for which timezone is used if none is explicitly mentioned 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().