2013-12-14 07:11:37 +00:00
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# frac
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Rational approximation to a floating point number with bounded denominator.
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Uses the Mediant Method <https://en.wikipedia.org/wiki/Mediant_(mathematics)>
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2013-12-25 04:06:06 +00:00
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This module also provides an implementation of the continued fraction method as
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described by Aberth in "A method for exact computation with rational numbers",
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which appears to be used by spreadsheet programs for displaying fractions
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2013-12-14 07:11:37 +00:00
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## JS Installation and Usage
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In node:
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$ npm install frac
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In the browser:
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<script src="frac.js"></script>
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The exported `frac` function takes three arguments:
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- `x` the number we wish to approximate
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- `D` the maximum denominator
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- `mixed` if true, return a mixed fraction (default); if false, improper
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The return value is an array of the form `[quot, num, den]` where `quot==0`
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for improper fractions.
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For example:
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```
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> // var frac = require('frac'); // uncomment this line if in node
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> frac(Math.PI,100) // [ 0, 22, 7 ]
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> frac(Math.PI,100,true) // [ 3, 1, 7 ]
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```
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2013-12-25 04:06:06 +00:00
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`frac.cont` implements the Aberth algorithm (input and output specifications
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match the original `frac` function)
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