<variablelist>
<varlistentry>
- <term>ST_Distance(geometry, geometry)</term>
+ <term>ST_Distance(A geometry, B geometry)</term>
<listitem>
<para>Return the cartesian distance between two geometries in
</varlistentry>
<varlistentry>
- <term>ST_DWithin(geometry, geometry, float)</term>
+ <term>ST_DWithin(A geometry, B geometry, sriddistance float)</term>
<listitem>
- <para>Returns true if geometries are within the specified distance
- of one another. Uses indexes if available.</para>
+ <para>Returns true if geometries are within the specified sriddistance
+ of one another. sriddistance is in units defined by the spatial reference system.
+ Uses indexes if available.</para>
</listitem>
</varlistentry>
<term>ST_Equals(geometry, geometry)</term>
<listitem>
- <para>Returns 1 (TRUE) if the given Geometries are "spatially
+ <para>Returns TRUE if the given Geometries are "spatially
equal". Use this for a 'better' answer than '='.
equals('LINESTRING(0 0, 10 10)','LINESTRING(0 0, 5 5, 10 10)') is
- true.</para>
+ true. Note by spatially equal we also mean ordering of points can be different but
+ represent the same geometry structure. To verify the order of points is consistent, use
+ ST_OrderingEquals.</para>
<para>Performed by the GEOS module</para>
</varlistentry>
<varlistentry>
- <term>ST_Disjoint(geometry, geometry)</term>
+ <term>ST_Disjoint(A geometry, B geometry)</term>
<listitem>
- <para>Returns 1 (TRUE) if the Geometries are "spatially
+ <para>Returns TRUE if the Geometries are "spatially
disjoint".</para>
<para>Performed by the GEOS module</para>
</varlistentry>
<varlistentry>
- <term>ST_Intersects(geometry, geometry)</term>
+ <term>ST_Intersects(A geometry, B geometry)</term>
<listitem>
- <para>Returns 1 (TRUE) if the Geometries "spatially
- intersect".</para>
+ <para>Returns TRUE if the Geometries "spatially
+ intersect" - (share any portion of space) and FALSE if they don't.</para>
<para>Performed by the GEOS module</para>
</varlistentry>
<varlistentry>
- <term>ST_Touches(geometry, geometry)</term>
+ <term>ST_Touches(A geometry, B geometry)</term>
<listitem>
- <para>Returns 1 (TRUE) if the Geometries "spatially touch".</para>
+ <para>Returns TRUE if the Geometries "spatially touch".</para>
<para>Performed by the GEOS module</para>
</varlistentry>
<varlistentry>
- <term>ST_Crosses(geometry, geometry)</term>
+ <term>ST_Crosses(A geometry, B geometry)</term>
<listitem>
- <para>Returns 1 (TRUE) if the Geometries "spatially cross".</para>
+ <para>Returns TRUE if the Geometries "spatially cross".</para>
<para>Performed by the GEOS module</para>
</varlistentry>
<varlistentry>
- <term>ST_Within(geometry A, geometry B)</term>
+ <term>ST_Within(A geometry, B geometry)</term>
<listitem>
- <para>Returns 1 (TRUE) if Geometry A is "spatially within"
+ <para>Returns TRUE if Geometry A is "spatially within"
Geometry B. A has to be completely inside B.</para>
<para>Performed by the GEOS module</para>
</varlistentry>
<varlistentry>
- <term>ST_Overlaps(geometry, geometry)</term>
+ <term>ST_Overlaps(A geometry, B geometry)</term>
<listitem>
- <para>Returns 1 (TRUE) if the Geometries "spatially
+ <para>Returns TRUE if the Geometries "spatially
overlap".</para>
<para>Performed by the GEOS module</para>
</varlistentry>
<varlistentry>
- <term>ST_Contains(geometry A, geometry B)</term>
+ <term>ST_Contains(A geometry, B geometry)</term>
<listitem>
- <para>Returns 1 (TRUE) if Geometry A "spatially contains" Geometry
+ <para>Returns TRUE if Geometry A "spatially contains" Geometry
B.</para>
<para>Performed by the GEOS module</para>