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@@ -5,7 +5,8 @@ analysis classifier. It can be used to perform the second
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step in either an unsupervised or a supervised image
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classification.
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-<p>Either image classification methods are performed in two
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+<p>
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+Either image classification methods are performed in two
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steps. The first step in an unsupervised image
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classification is performed by
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<em><a href="i.cluster.html">i.cluster</a></em>; the
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@@ -15,7 +16,8 @@ the GRASS program <em>
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the second step in the image classification procedure is
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performed by <em>i.maxlik</em>.
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-<p>In an unsupervised classification, the maximum-likelihood
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+<p>
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+In an unsupervised classification, the maximum-likelihood
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classifier uses the cluster means and covariance matrices
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from the <em><a href="i.cluster.html">i.cluster</a></em>
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signature file to determine to which category (spectral
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@@ -29,13 +31,15 @@ generated by <em>
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to which category each cell in the image has the highest
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probability of belonging.
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-<p>In either case, the raster map layer output by
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+<p>
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+In either case, the raster map layer output by
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<em>i.maxlik</em> is a classified image in which each cell
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has been assigned to a spectral class (i.e., a category).
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The spectral classes (categories) can be related to
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specific land cover types on the ground.
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-<p>The program will run non-interactively if the user
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+<p>
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+The program will run non-interactively if the user
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specifies the names of raster map layers, i.e., group and
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subgroup names, seed signature file name, result
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classification file name, and any combination of
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@@ -57,20 +61,8 @@ in the command line without program arguments. In this case
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the user will be prompted for the program parameter
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settings; the program will run foreground.
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-
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<h2>OPTIONS</h2>
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-
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-<h3>Flags:</h3>
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-
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-<dl>
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-
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-<dt><b>-q</b>
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-
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-<dd>Run quietly, without printing program messages to standard output.
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-
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-</dl>
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-
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<h3>Parameters:</h3>
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<dl>
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@@ -120,7 +112,6 @@ each classified cell in the classified image. One of the
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possible uses for this map layer is as a mask, to identify
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cells in the classified image that have the lowest
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probability of being assigned to the correct class.
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-
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</dl>
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@@ -140,12 +131,28 @@ If this occurs,
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<em>i.maxlik</em>
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will reject them and display a warning message.
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-<p>This program runs interactively if the user types
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+<p>
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+This program runs interactively if the user types
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<em>i.maxlik</em> only. If the user types <em>i.maxlik</em>
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along with all required options, it will overwrite the
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classified raster map without prompting if this map
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existed.
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+<h2>EXAMPLE</h2>
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+
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+Completion of the unsupervised classification of
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+a LANDSAT subscene (VIZ, NIR, MIR channels) in North Carolina
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+(see <em>i.cluster</em> manual page for the first part):
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+
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+<div class="code"><pre>
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+i.maxlik group=my_lsat7_2002 subgroup=my_lsat7_2002 sigfile=sig_clust_lsat2002 \
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+ class=lsat7_2002_clust_classes reject=lsat7_2002_clust_classes.rej
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+
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+# Visually check result
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+d.mon wx0
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+d.rast.leg lsat7_2002_clust_classes
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+d.rast.leg lsat7_2002_clust_classes.rej
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+</pre></div>
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<h2>SEE ALSO</h2>
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@@ -153,11 +160,13 @@ The GRASS 4 <em>
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<a href="http://grass.osgeo.org/gdp/imagery/grass4_image_processing.pdf">Image
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Processing manual</a></em>
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-<p><em>
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+<p>
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+<em>
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<a href="i.class.html">i.class</a>,
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<a href="i.cluster.html">i.cluster</a>,
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<a href="i.gensig.html">i.gensig</a>,
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-<a href="i.group.html">i.group</a>
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+<a href="i.group.html">i.group</a>,
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+<a href="r.kappa.html">r.kappa</a>
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</em>
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<h2>AUTHORS</h2>
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@@ -171,4 +180,5 @@ Tao Wen,
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University of Illinois at Urbana-Champaign,
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Illinois
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-<p><i>Last changed: $Date$</i>
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+<p>
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+<i>Last changed: $Date$</i>
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