</varlistentry>
<varlistentry>
<term><parameter>reclassexpr </parameter><type>text</type></term>
- <listitem><para>Mathemetical expression defining how to map band to new band.</para></listitem>
+ <listitem><para>range expression consisting of - (define range) and : to define mapping that defines how to map old band values to new band values. ( means >, ) means less than, ] < or equal, [ means > or equal</para></listitem>
</varlistentry>
<varlistentry>
<term><parameter>pixeltype </parameter><type>text</type></term>
<listitem><para>One of defined pixel types as described in <xref linkend="RT_ST_BandPixelType" /></para></listitem>
</varlistentry>
+ <varlistentry>
+ <term><parameter>nodataval </parameter><type>double precision</type></term>
+ <listitem><para>Value to treat as no data. For image outputs that support transparency, these will be blank.</para></listitem>
+ </varlistentry>
</variablelist>
</refsection>
<refsection>
<title>Example: Reclassify band 2 as an 8BUI where 255 is nodata value</title>
<programlisting>SELECT ROW(2, '0-100:1-10, 101-500:11-150,501 - 10000: 151-254', '8BUI', 255)::reclassarg;</programlisting>
+ </refsection>
+ <refsection>
+ <title>Example: Reclassify band 1 as an 1BB and no nodata value defined</title>
+ <programlisting>SELECT ROW(2, '0-100]:0, (100-255:1', '1BB', NULL)::reclassarg;</programlisting>
</refsection>
<refsection>
<title>See Also</title>
<para><xref linkend="RT_ST_Reclass" /></para>
</refsection>
</refentry>
+
+ <refentry id="summarystats">
+ <refnamediv>
+ <refname>summarystats</refname>
+ <refpurpose>A composite type used as output the ST_SummaryStats function.</refpurpose>
+ </refnamediv>
+ <refsection>
+ <title>Description</title>
+ <para>A composite type used as output the ST_SummaryStats function. Note that depending on <varname>exclude_nodata_value</varname> of function, may or may not contain nodata pixels.</para>
+ <variablelist>
+ <varlistentry>
+ <term><parameter>count </parameter><type>bigint</type></term>
+ <listitem><para>count of pixels in raster band. Depending on arguments may or many not include nodata pixel values.</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>sum </parameter><type>double precision</type></term>
+ <listitem><para>sum of all pixel values in band</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>mean </parameter><type>double precision</type></term>
+ <listitem><para>Mean of pixel values</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>stddev </parameter><type>double precision</type></term>
+ <listitem><para>Standard deviation of pixel values.</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>min </parameter><type>double precision</type></term>
+ <listitem><para>Minimum pixel value</para></listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>max </parameter><type>double precision</type></term>
+ <listitem><para>Maximum pixel value</para></listitem>
+ </varlistentry>
+ </variablelist>
+ </refsection>
+ <refsection>
+ <title>See Also</title>
+ <para><xref linkend="RT_ST_SummaryStats" /></para>
+ </refsection>
+ </refentry>
</sect1>
<sect1 id="Raster_Management_Functions">
<title>Raster Management Functions</title>
<refsection>
<title>See Also</title>
- <para><xref linkend="RT_ST_Count" /></para>
+ <para><xref linkend="RT_ST_Count" />, <para><xref linkend="summarystats" /></para></para>
</refsection>
</refentry>
</refsection>
<refsection>
- <title>Examples</title>
+ <title>Examples Basic</title>
<para>Create a new raster from the original where band 2 is converted from 8BUI to 4BUI and all values from 251-255 are set to nodata value.</para>
<programlisting>ALTER TABLE dummy_rast ADD COLUMN reclass_rast raster;
UPDATE dummy_rast SET reclass_rast = ST_Reclass(rast,2,'0-87:1-10, 88-100:11-15, 101-254:0-0', '4BUI',0) WHERE rid = 2;
-SELECT i as row, j as col, ST_Value(rast,2,i,j) As origval,
+SELECT i as col, j as row, ST_Value(rast,2,i,j) As origval,
ST_Value(reclass_rast, 2, i, j) As reclassval,
ST_Value(reclass_rast, 2, i, j, false) As reclassval_include_nodata
FROM dummy_rast CROSS JOIN generate_series(1, 3) AS i CROSS JOIN generate_series(1,3) AS j
WHERE rid = 2;
- row | col | origval | reclassval | reclassval_include_nodata
+ col | row | origval | reclassval | reclassval_include_nodata
-----+-----+---------+------------+---------------------------
1 | 1 | 78 | 9 | 9
2 | 1 | 98 | 14 | 14
3 | 3 | 169 | | 0</programlisting>
<!-- TODO: Add more examples using reclass arg -->
</refsection>
+
+ <refsection>
+ <title>Example: Advanced using multiple reclassargs</title>
+
+ <para>Create a new raster from the original where band 1,2,3 is converted to 1BB,4BUI, 4BUI respectively and reclassified.
+ Note this uses the variadic <varname>reclassarg</varname> argument which can take as input an indefinite number of reclassargs (theoretically as many bands as you have) </para>
+ <programlisting>UPDATE dummy_rast SET reclass_rast =
+ ST_Reclass(rast,
+ ROW(2,'0-87]:1-10, (87-100]:11-15, (101-254]:0-0', '4BUI',NULL)::reclassarg,
+ ROW(1,'0-253]:1, 254:0', '1BB', NULL)::reclassarg,
+ ROW(3,'0-70]:1, (70-86:2, [86-150):3, [150-255:4', '4BUI', NULL)::reclassarg
+ ) WHERE rid = 2;
+
+SELECT i as col, j as row,ST_Value(rast,1,i,j) As ov1, ST_Value(reclass_rast, 1, i, j) As rv1,
+ ST_Value(rast,2,i,j) As ov2, ST_Value(reclass_rast, 2, i, j) As rv2,
+ ST_Value(rast,3,i,j) As ov3, ST_Value(reclass_rast, 3, i, j) As rv3
+FROM dummy_rast CROSS JOIN generate_series(1, 3) AS i CROSS JOIN generate_series(1,3) AS j
+WHERE rid = 2;
+
+col | row | ov1 | rv1 | ov2 | rv2 | ov3 | rv3
+----+-----+-----+-----+-----+-----+-----+-----
+ 1 | 1 | 253 | 1 | 78 | 9 | 70 | 1
+ 2 | 1 | 254 | 0 | 98 | 14 | 86 | 3
+ 3 | 1 | 253 | 1 | 122 | 0 | 100 | 3
+ 1 | 2 | 253 | 1 | 96 | 14 | 80 | 2
+ 2 | 2 | 254 | 0 | 118 | 0 | 108 | 3
+ 3 | 2 | 254 | 0 | 180 | 0 | 162 | 4
+ 1 | 3 | 250 | 1 | 99 | 15 | 90 | 3
+ 2 | 3 | 254 | 0 | 112 | 0 | 108 | 3
+ 3 | 3 | 254 | 0 | 169 | 0 | 175 | 4</programlisting>
+ </refsection>
<refsection>
<title>See Also</title>
- <para><xref linkend="RT_ST_BandPixelType" />, <xref linkend="reclassarg" /></para>
+ <para><xref linkend="RT_ST_BandPixelType" />, <xref linkend="reclassarg" />, <para><xref linkend="RT_ST_Value" /></para></para>
</refsection>
</refentry>
</sect1>
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