43 lines
1.2 KiB
HTML
43 lines
1.2 KiB
HTML
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<html>
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<body BGCOLOR="#00E0E0" link="#001fC0" vlink="#000080" text="#00000f">
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<h1><title> BC - Bench Calculator </title></h1>
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<h1> BC - Bench Calculator </h1>
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<h3>'bc' is a unix scripting tool that provides 'arbitary precision'
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mathematics.</h3>
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<p>
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It has a 'C' like syntax, supports recursion and allows
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variables and functions to
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be defined (although as the old bc only allowed single letter names
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I have carried on using this).
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</p>
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<p>
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An example of bc in action can be seen in <a href="pi.php"> calculate pi with arbitary precision </a>.
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</p>
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<p>
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In this project it is used via php scripts, to provide
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the mathematical muscle to deal with the very large numbers
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handled in RSA implementations.
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It is still a little slow, and the cpu load will
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regularly hit 95% as it calculates large exponents.
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Very large values may even cause the page to take minutes
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to complete calculations.
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However, the numbers used in RSA are so large that
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double precision, or floating point, is woefully inadequate.
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</p>
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Link to unix <a href="bc_man_page.html"> bc man page </a> converted to html.
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<br>
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<br>
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<center>
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<a href="javascript:history.back();">
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<img src=back.png align=center border=0> </a>
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</center>
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</body>
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</html>
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