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21 lines
3.5 KiB
HTML
21 lines
3.5 KiB
HTML
<html>
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<head><link rel="stylesheet" type="text/css" href="help.css" /></head>
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<body>
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<h1 class='module'>Zonal Grid Statistics</h1>
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<div class='author'>Copyrights (c) 2005 by Volker Wichmann</div>
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<div class='description'>The module calculates zonal statistics and reports these in a table. The module can be used to create a contingency table of unique condition units (UCUs). These units are delineated from a zonal grid (e.g. sub catchments) and optional categorial grids (e.g. landcover, soil, ...). It is possible to calculate simple statistics (min, max, mean, standard deviation and sum) for each UCU from optional grids with continious data (e.g. slope; aspect must be handled specially, please use the "Aspect" input parameter for such a grid). The number of input grids is only limited by available memory. The module has four different modes of application: (1) only a zonal grid is used as input. This results in a simple contingency table with the number of grid cells in each zone. (2) a zonal grid and additional categorial grids are used as input. This results in a contingency table with the number of cells in each UCU. (3) a zonal grid and additional grids with continuous data are used as input. This results in a contingency table with the number of cells in each zone and some simple statistics for each zone. The statistics are calculated for each continuous grid. (4) a zonal grid, additional categorial grids and additional grids with continuous data are used as input. This results in a contingency table with the number of cells in each UCU and the corresponding statistics for each continuous grid.<br/>
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<br/>
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Depending on the mode of application, the output table contains information about the category combination of each UCU, the number of cells in each UCU and the statistics for each UCU. A typical output table may look like this:<br/>
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<table border="1"><tr><td>ID Zone</td><td>ID 1stCat</td><td>ID 2ndCat</td><td>Count UCU</td><td>MIN 1stCont</td><td>MAX 1stCont</td><td>MEAN 1stCont</td><td>STDDEV 1stCont</td><td>SUM 1stCont</td></tr><tr><td>0 </td><td>2 </td><td>6 </td><td>6 </td><td>708.5 </td><td>862.0 </td><td>734.5 </td><td>62.5 </td><td>4406.8 </td></tr><tr><td>0 </td><td>3 </td><td>4 </td><td>106 </td><td>829.1 </td><td>910.1 </td><td>848.8 </td><td>28.5 </td><td>89969.0 </td></tr></table></div>
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<h2>Parameters</h2>
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<dl class='parameters'>
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<dt>Grid system <div class='type'>Grid system</div></dt><dd>Grid system <div class='constraints'></div></dd>
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<dt>Zone Grid <div class='type'>Input Grid</div></dt><dd>Grid defining the zones to analyse. This grid also acts as a mask. Coding: no-data / categorial values. <div class='constraints'></div></dd>
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<dt>Categorial Grids <div class='type'>Input Grid list</div></dt><dd>Grids used to delineate the UCUs. Coding: no-data / categorial values. <div class='constraints'></div></dd>
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<dt>Grids to analyse <div class='type'>Input Grid list</div></dt><dd>Grids with continuous data, statistics are calculated for each grid. Coding: no-data / continuous values. <div class='constraints'></div></dd>
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<dt>Aspect <div class='type'>Input Grid</div></dt><dd>Aspect grid, in radians. <div class='constraints'></div></dd>
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<dt>Zonal Statistics <div class='type'>Output Table</div></dt><dd>Summary table. <div class='constraints'></div></dd>
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<dt>Short Field Names <div class='type'>Boolean</div></dt><dd> <div class='constraints'></div></dd>
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</dl>
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</body></html>
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