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44 lines
2.4 KiB
HTML
44 lines
2.4 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'>Point Cloud Attribute Calculator</h1>
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<div class='author'>Volker Wichmann (c) 2010, LASERDATA GmbH</div>
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<div class='description'>The Point Cloud Attribute Calculator calculates a new attribute based on existing attributes and a mathematical formula. The attribute fields are referenced by characters 'a' to 'z' with 'a' referencing the first field, 'b' the second field and so on. Please note that the first three fields contain the x,y,z coordinates.<br/>
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This (meaningless) example calculates the sine of the x coordinate and multiplies it with the z coordinate: sin(a) * c<br/>
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<br/>
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The following operators are available for the formula definition:<br/>
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+ Addition<br/>
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- Subtraction<br/>
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* Multiplication<br/>
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/ Division<br/>
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^ power<br/>
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abs(x) - absolute value<br/>
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sqrt(x) - square root<br/>
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ln(x) - natural logarithm<br/>
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log(x) - base 10 logarithm<br/>
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exp(x) - exponential<br/>
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sin(x) - sine<br/>
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cos(x) - cosine<br/>
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tan(x) - tangent<br/>
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asin(x) - arcsine<br/>
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acos(x) - arccosine<br/>
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atan(x) - arctangent<br/>
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atan2(x, y) - arctangent of x/y<br/>
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gt(x, y) - if x>y the result is 1.0, else 0.0<br/>
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lt(x, y) - if x<y the result is 1.0, else 0.0<br/>
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eq(x, y) - if x=y the result is 1.0, else 0.0<br/>
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mod(x, y) - returns the floating point remainder of x/y<br/>
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ifelse(c, x, y) - if c=1 the result is x, else y<br/>
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int(x) - integer part of floating point value x<br/>
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pi() - returns the value of Pi<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>Point Cloud <div class='type'>Input Point Cloud</div></dt><dd>Input <div class='constraints'></div></dd>
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<dt>Result <div class='type'>Output Point Cloud</div></dt><dd>Output <div class='constraints'></div></dd>
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<dt>Formula <div class='type'>Text</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Output Field Name <div class='type'>Text</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Field data type <div class='type'>Choice</div></dt><dd> <div class='constraints'>Available choices: 1 bit, 1 byte unsigned integer, 1 byte signed integer, 2 byte unsigned integer, 2 byte signed integer, 4 byte unsigned integer, 4 byte signed integer, 4 byte floating point, 8 byte floating point</div></dd>
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</dl>
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</body></html>
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