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<h2>NAME</h2>
<em><b>r.what.color</b></em> - Queries colors for a raster map layer.
<h2>KEYWORDS</h2>
raster
<h2>SYNOPSIS</h2>
<b>r.what.color</b><br>
<b>r.what.color help</b><br>
<b>r.what.color</b> [-<b>i</b>] <b>input</b>=<em>string</em> [<b>value</b>=<em>float</em>[,<i>float</i>,...]] [<b>format</b>=<em>string</em>] [--<b>verbose</b>] [--<b>quiet</b>]
<h3>Flags:</h3>
<DL>
<DT><b>-i</b></DT>
<DD>Read values from stdin</DD>
<DT><b>--verbose</b></DT>
<DD>Verbose module output</DD>
<DT><b>--quiet</b></DT>
<DD>Quiet module output</DD>
</DL>
<h3>Parameters:</h3>
<DL>
<DT><b>input</b>=<em>string</em></DT>
<DD>Name of existing raster map to query colors</DD>
<DT><b>value</b>=<em>float[,<i>float</i>,...]</em></DT>
<DD>Values to query colors for</DD>
<DT><b>format</b>=<em>string</em></DT>
<DD>Output format (printf-style)</DD>
<DD>Default: <em>%d:%d:%d</em></DD>
</DL>
<H2>DESCRIPTION</H2>
<EM>r.what.color</EM> outputs the color associated with user-specified
category values in a raster input map.
<p>
Values may be specified either using the <b>values=</b> option, or by
specifying the <b>-i</b> flag and passing the values on
<tt>stdin</tt>, one per line.
<p>
For each value which is specified, a line of output will be generated
consisting of the category value followed by the color, e.g.:
<div class="code"><pre>
r.what.color input=elevation.dem value=1500
1500: 223:127:31
</pre></div>
<p>
If the input map is an integer (CELL) map, the category will be
written as an integer (no decimal point), otherwise it will be written
in floating point format (<i>printf("%f")</i> format).
<p>
If the lookup fails for a value, the color will be output as an
asterisk, e.g.:
<div class="code"><pre>
r.what.color input=elevation.dem value=9999
9999: *
</pre></div>
<p>
If a value cannot be parsed, both the value and the color will be
output as an asterisk, e.g.:
<div class="code"><pre>
r.what.color input=elevation.dem value=bogus
*: *
</pre></div>
<p>
The format can be changed using the <b>format=</b> option. The value
should be a <i>printf()</i>-style format string containing three
conversion specifiers for the red, green and blue values respectively,
e.g.:
<div class="code"><pre>
r.what.color input=elevation.dem value=1500 format='%02x:%02x:%02x'
1500: df:7f:1f
</pre></div>
<p>
If your system supports the <i>%m$</i> syntax, you can change the
ordering of the components, e.g.:
<div class="code"><pre>
r.what.color input=elevation.dem value=1500 format='%3$02x:%2$02x:%1$02x'
1500: 1f:7f:df
</pre></div>
<P>
Common formats:<BR>
<ul>
<li>Tcl/Tk: <tt>format="#%02x%02x%02x"</tt>
<li>WxPython: <tt>format='"#%02x%02x%02x"'</tt> or <tt>format='"(%d,%d,%d)"'</tt>
</ul>
<H2>SEE ALSO</H2>
<EM>
<A HREF="r.what.html">r.what</A>
</EM>
<H2>AUTHOR</H2>
Glynn Clements
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