value is in radians. Angle is computed clockwise from down-to-up: on the clock: 12=0; 3=PI/2; 6=PI; 9=3PI/4 </para>
<para>The Azimuth is mathematical concept defined as the angle, in this case measured in radian, between a reference plane
- and a point</para>
+ and a point. </para>
<para>Availability: 1.1.0</para>
<para>Azimuth is especially useful in conjunction with ST_Translate for shifting an object along its perpendicular axis. See
- upgis_lineshift <ulink url="http://www.postgis.org/support/wiki/index.php?plpgsqlfunctions">Plpgsqlfunctions PostGIS wiki section</ulink> for example of this.</para>
+ upgis_lineshift <ulink url="http://trac.osgeo.org/postgis/wiki/UsersWikiplpgsqlfunctions">Plpgsqlfunctions PostGIS wiki section</ulink> for example of this.</para>
</refsection>
<refsection>
<title>Examples</title>
- <para>--Azimuth in degrees </para>
+ <para>Azimuth in degrees </para>
<programlisting>
SELECT ST_Azimuth(ST_Point(25,45), ST_Point(75,100))/(2*pi())*360 as degAz,
ST_Azimuth(ST_Point(75,100), ST_Point(25,45))/(2*pi())*360 As degAzrev;
<imageobject>
<imagedata fileref="images/st_azimuth01.png" />
</imageobject>
- <caption><para>degAz is curve shown with horizontal and points</para></caption>
+ <caption><para>degAz is path to travel (azimuth), horizontal line (which starts at the start point and ends where we want the end point to fall)
+ and points (start point: 25,45 is in green)</para></caption>
</mediaobject>
</informalfigure>
</para></entry>
<imageobject>
<imagedata fileref="images/st_azimuth02.png" />
</imageobject>
- <caption><para>degAzrev is azimuth curve shown with horizontal and points</para></caption>
+ <caption><para>degAzrev is azimuth curve shown, horizontal line (which starts at the start point and ends where we want the end point to fall)
+ and points (start point: 75,100 is in green)</para></caption>
</mediaobject>
</informalfigure>
</para></entry>