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43 lines
3.8 KiB
HTML
43 lines
3.8 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'>Cubic Spline Approximation</h1>
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<div class='author'>O. Conrad (c) 2008</div>
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<div class='description'>This module approximates irregular scalar 2D data in specified points using C1-continuous bivariate cubic spline.<br/>
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Minimal Number of Points: minimal number of points locally involved in spline calculation (normally = 3)<br/>
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<br/>
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Maximal Number of Points:npmax: maximal number of points locally involved in spline calculation (required > 10, recommended 20 < npmax < 60)<br/>
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Tolerance: relative tolerance multiple in fitting spline coefficients: the higher this value, the higher degree of the locally fitted spline (recommended 80 < k < 200)<br/>
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<br/>
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Points per square: average number of points per square (increase if the point distribution is strongly non-uniform to get larger cells)<br/>
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<br/>
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Author: Pavel Sakov, CSIRO Marine Research<br/>
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<br/>
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Purpose: 2D data approximation with bivariate C1 cubic spline. A set of library functions + standalone utility.<br/>
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<br/>
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Description: See J. Haber, F. Zeilfelder, O.Davydov and H.-P. Seidel, Smooth approximation and rendering of large scattered data sets, in 'Proceedings of IEEE Visualization 2001' (Th.Ertl, K.Joy and A.Varshney, Eds.), pp.341-347, 571, IEEE Computer Society, 2001.<br/>
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<a target="_blank" href="http://www.uni-giessen.de/www-Numerische-Mathematik/davydov/VIS2001.ps.gz">www.uni-giessen.de/www-Numerische-Mathematik/davydov/VIS2001.ps.gz</a><br/>
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<a target="_blank" href="http://www.math.uni-mannheim.de/~lsmath4/paper/VIS2001.pdf.gz">www.math.uni-mannheim.de/~lsmath4/paper/VIS2001.pdf.gz</a><br/>
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</div>
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<h2>Parameters</h2>
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<dl class='parameters'>
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<dt>Points <div class='type'>Input Shapes</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Attribute <div class='type'>Table field</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Target Grid <div class='type'>Choice</div></dt><dd> <div class='constraints'>Available choices: user defined, grid</div></dd>
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<dt>Minimal Number of Points <div class='type'>Integer</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Maximal Number of Points <div class='type'>Integer</div></dt><dd> <div class='constraints'>Minimum: 11.0; Maximum: 59.0</div></dd>
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<dt>Points per Square <div class='type'>Floating point</div></dt><dd> <div class='constraints'>Minimum: 1.0</div></dd>
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<dt>Tolerance <div class='type'>Integer</div></dt><dd>Spline sensitivity, reduce to get smoother results, recommended: 80 < Tolerance < 200 <div class='constraints'></div></dd>
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<dt>Left <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Right <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Bottom <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Top <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Cellsize <div class='type'>Floating point</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Columns <div class='type'>Integer</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Rows <div class='type'>Integer</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Grid <div class='type'>Output Data Object</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Grid system <div class='type'>Grid system</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Grid <div class='type'>Output Grid</div></dt><dd> <div class='constraints'></div></dd>
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</dl>
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</body></html>
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