blitz-research
74 lines
1.6 KiB
HTML
74 lines
1.6 KiB
HTML
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<title>Blitz3D Docs</title>
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<link rel=stylesheet href=../css/commands.css type=text/css>
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<h1>Log# ( x# )</h1>
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<h1>Parameters</h1>
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x = any positive number.
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</td>
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<h1>Description</h1>
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Natural logarithm of x. This is the inverse of Exp( ).
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y = Log( x ) means y satifies x = Exp( y ).
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The base of the natural logarithm is e = Exp(1) = 2.71828...
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See also Exp()
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<h1><a href=../2d_examples/Log.bb>Example</a></h1>
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; Log example
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; NaN means "Not a Number", the numerical result is invalid.
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; NOTE: All logarithm functions are related. For example, there is no
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; Log8 function in Blitz, but we can easily make one.
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HidePointer
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Print "Log8( -1 ) = " + Log8( -1 )
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Print "Log8( 0 ) = " + Log8( 0 )
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Print
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; ... and now some well behaved numbers...
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x# = 1.0 / 4096.0 ; small positive number
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For n = 1 To 15
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Print "Log8( " + LSet( x, 13 ) + " ) = " + Log8( x )
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x = 8 * x
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Next
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WaitKey() : End
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Function Log8# ( x# )
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Return Log( x ) / Log( 8 )
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End Function
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</tr>
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</table>
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<br>
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<a target=_top href=../index.htm>Index</a><br>
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<br>
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Click <a href=http://www.blitzbasic.co.nz/b3ddocs/command.php?name=Log&ref=comments target=_blank>here</a> to view the latest version of this page online</body>
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</html>
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