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45 lines
1.9 KiB
HTML
45 lines
1.9 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'>Table Calculator</h1>
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<div class='author'>V.Olaya (c) 2004, O.Conrad (c) 2011</div>
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<div class='description'>The table calculator calculates a new attribute from existing attributes based on a mathematical formula. Attributes are addressed by the character 'f' (for 'field') followed by the field number (i.e.: f1, f2, ..., fn) or by the field name in square brackets (e.g.: [Field Name]).<br/>
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Examples:<br/>
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sin(f1) * f2 + f3<br/>
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[Population] / [Area]<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>Formula <div class='type'>Text</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Field Name <div class='type'>Text</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Table <div class='type'>Input Table</div></dt><dd> <div class='constraints'></div></dd>
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<dt>Result <div class='type'>Output Table</div></dt><dd> <div class='constraints'></div></dd>
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</dl>
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</body></html>
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