<?xml version="1.0" encoding="utf-8"?>
<!-- $Revision$ -->
<refentry xml:id="function.date-sunrise" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
 <refnamediv>
  <refname>date_sunrise</refname>
  <refpurpose>Returns time of sunrise for a given day and location</refpurpose>
 </refnamediv>

 <refsynopsisdiv>
  <warning>
   <para>
    This function has been <emphasis>DEPRECATED</emphasis> as of PHP 8.1.0.
    Relying on this function is highly discouraged. Use
    <function>date_sun_info</function> instead.
   </para>
  </warning>
 </refsynopsisdiv>

 <refsect1 role="description">
  &reftitle.description;
  <methodsynopsis>
   <type class="union"><type>string</type><type>int</type><type>float</type><type>false</type></type><methodname>date_sunrise</methodname>
   <methodparam><type>int</type><parameter>timestamp</parameter></methodparam>
   <methodparam choice="opt"><type>int</type><parameter>returnFormat</parameter><initializer><constant>SUNFUNCS_RET_STRING</constant></initializer></methodparam>
   <methodparam choice="opt"><type class="union"><type>float</type><type>null</type></type><parameter>latitude</parameter><initializer>&null;</initializer></methodparam>
   <methodparam choice="opt"><type class="union"><type>float</type><type>null</type></type><parameter>longitude</parameter><initializer>&null;</initializer></methodparam>
   <methodparam choice="opt"><type class="union"><type>float</type><type>null</type></type><parameter>zenith</parameter><initializer>&null;</initializer></methodparam>
   <methodparam choice="opt"><type class="union"><type>float</type><type>null</type></type><parameter>utcOffset</parameter><initializer>&null;</initializer></methodparam>
  </methodsynopsis>
  <para>
   <function>date_sunrise</function> returns the sunrise time for a given
   day (specified as a <parameter>timestamp</parameter>) and location.
  </para>
 </refsect1>

 <refsect1 role="parameters">
  &reftitle.parameters;
  <para>
   <variablelist>
    <varlistentry>
     <term><parameter>timestamp</parameter></term>
     <listitem>
      <para>
       The <parameter>timestamp</parameter> of the day from which the sunrise
       time is taken.
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>returnFormat</parameter></term>
     <listitem>
      <para>
       <table>
        <title><parameter>returnFormat</parameter> constants</title>
        <tgroup cols="2">
         <thead>
          <row>
           <entry>constant</entry>
           <entry>description</entry>
           <entry>example</entry>
          </row>
         </thead>
         <tbody>
          <row>
           <entry>SUNFUNCS_RET_STRING</entry>
           <entry>returns the result as <type>string</type></entry>
           <entry>16:46</entry>
          </row>
          <row>
           <entry>SUNFUNCS_RET_DOUBLE</entry>
           <entry>returns the result as <type>float</type></entry>
           <entry>16.78243132</entry>
          </row>
          <row>
           <entry>SUNFUNCS_RET_TIMESTAMP</entry>
           <entry>returns the result as <type>int</type> (timestamp)</entry>
           <entry>1095034606</entry>
          </row>
         </tbody>
        </tgroup>
       </table>
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>latitude</parameter></term>
     <listitem>
      <para>
       Defaults to North, pass in a negative value for South.
       See also: <link linkend="ini.date.default-latitude">date.default_latitude</link>
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>longitude</parameter></term>
     <listitem>
      <para>
       Defaults to East, pass in a negative value for West.
       See also: <link linkend="ini.date.default-longitude">date.default_longitude</link>
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>zenith</parameter></term>
     <listitem>
      <para>
       <parameter>zenith</parameter> is the angle between the center of the sun
       and a line perpendicular to earth's surface. It defaults to
       <link linkend="ini.date.sunrise-zenith">date.sunrise_zenith</link>
       <table>
        <title>Common <parameter>zenith</parameter> angles</title>
        <tgroup cols="2">
         <thead>
          <row>
           <entry>Angle</entry>
           <entry>Description</entry>
          </row>
         </thead>
         <tbody>
          <row>
           <entry>90°50'</entry>
           <entry>Sunrise: the point where the sun becomes visible.</entry>
          </row>
          <row>
           <entry>96°</entry>
           <entry>Civil twilight: conventionally used to signify the start of dawn.</entry>
          </row>
          <row>
           <entry>102°</entry>
           <entry>Nautical twilight: the point at which the horizon starts being visible at sea.</entry>
          </row>
          <row>
           <entry>108°</entry>
           <entry>Astronomical twilight: the point at which the sun starts being the source of any illumination.</entry>
          </row>
         </tbody>
        </tgroup>
       </table>
      </para>
     </listitem>
    </varlistentry>
    <varlistentry>
     <term><parameter>utcOffset</parameter></term>
     <listitem>
      <para>
       Specified in hours.
       The <parameter>utcOffset</parameter> is ignored, if
       <parameter>returnFormat</parameter> is
       <constant>SUNFUNCS_RET_TIMESTAMP</constant>.
      </para>
     </listitem>
    </varlistentry>
   </variablelist>
  </para>
 </refsect1>

 <refsect1 role="returnvalues">
  &reftitle.returnvalues;
  <para>
   Returns the sunrise time in a specified <parameter>returnFormat</parameter> on
   success&return.falseforfailure;. One potential reason for failure is that the
   sun does not rise at all, which happens inside the polar circles for part of
   the year.
  </para>
 </refsect1>

 <refsect1 role="errors">
  &reftitle.errors;
   
   &date.timezone.errors.description;
 
 </refsect1>

 <refsect1 role="changelog">
  &reftitle.changelog;
  <para>
   <informaltable>
    <tgroup cols="2">
     <thead>
      <row>
       <entry>&Version;</entry>
       <entry>&Description;</entry>
      </row>
     </thead>
     <tbody>
      <row>
       <entry>8.1.0</entry>
       <entry>
        This function has been deprecated in favor of <function>date_sun_info</function>.
       </entry>
      </row>
      <row>
       <entry>8.0.0</entry>
       <entry>
        <parameter>latitude</parameter>, <parameter>longitude</parameter>,
        <parameter>zenith</parameter> and <parameter>utcOffset</parameter> are nullable now.
       </entry>
      </row>
     </tbody>
    </tgroup>
   </informaltable>
  </para>
 </refsect1>

 <refsect1 role="examples">
  &reftitle.examples;
  <para>
   <example>
    <title><function>date_sunrise</function> example</title>
    <programlisting role="php">
<![CDATA[
<?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);

?>
]]>
    </programlisting>
    &example.outputs.similar;
    <screen>
<![CDATA[
Mon Dec 20 2004, sunrise time : 08:54
]]>
    </screen>
   </example>
   <example>
    <title>No sunrise</title>
    <programlisting role="php">
<![CDATA[
<?php
$solstice = strtotime('2017-12-21');
var_dump(date_sunrise($solstice, SUNFUNCS_RET_STRING, 69.245833, -53.537222));
?>
]]>
    </programlisting>
    &example.outputs;
    <screen>
<![CDATA[
bool(false)
]]>
    </screen>
   </example>
  </para>
 </refsect1>

 <refsect1 role="seealso">
  &reftitle.seealso;
  <para>
   <simplelist>
    <member><function>date_sun_info</function></member>
   </simplelist>
  </para>
 </refsect1>
</refentry>
<!-- Keep this comment at the end of the file
Local variables:
mode: sgml
sgml-omittag:t
sgml-shorttag:t
sgml-minimize-attributes:nil
sgml-always-quote-attributes:t
sgml-indent-step:1
sgml-indent-data:t
indent-tabs-mode:nil
sgml-parent-document:nil
sgml-default-dtd-file:"~/.phpdoc/manual.ced"
sgml-exposed-tags:nil
sgml-local-catalogs:nil
sgml-local-ecat-files:nil
End:
vim600: syn=xml fen fdm=syntax fdl=2 si
vim: et tw=78 syn=sgml
vi: ts=1 sw=1
-->
