Posit numbers/decoding: Difference between revisions

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=={{header|Wren}}==

<syntaxhighlight lang="ecmascript">import "./fmt" for Conv

import "./~~rat~~" for ~~Rat~~

import "./big" for BigRat

var posit16_decode = Fn.new { |ps|

var posit16_decode = Fn.new { |ps, maxExpSize|

var p = ps.map { |c| c == "0" ? 0 : 1 }.toList

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}

var first = p[1]

var rs = 1 // regime size

var rs = 15 // regime size

for (i in 2..15) {

if (p[i] != first) {

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}

var regime = p[1..rs]

var es = 3.min(14-rs) // exponent size~~, maximum is 3.~~

var es = (rs == 15) ? 0 : maxExpSize.min(14-rs) // actual exponent size

var exponent = [0]

if (es > 0) exponent = p[rs + 2...rs + 2 + es]

var fs = 14 - rs - es // function size

var fs = (es == 0) ? 0 : 14 - rs - es // function size

var s = (p[0] == 0) ? 1 : -1 // sign

var k = regime.all { |i| i == 0 } ? -rs : rs - 1

var u = 2.pow(2.pow(es))

var u = 2.pow(2.pow(maxExpSize))

var e = Conv.atoi(exponent.join(""), 2)

var f = ~~Rat~~.~~zero~~

var f = BigRat.one

if (fs > 0) {

var fraction = ps[-fs..-1]

f = Conv.atoi(fraction.join(""), 2)

f = ~~Rat~~.one + ~~Rat~~.new(f, u)

f = BigRat.one + BigRat.new(f, 2.pow(fs))

}

return f * ~~Rat~~.new(u, 1).pow(k) * s * 2.pow(e)

return f * BigRat.new(u, 1).pow(k) * s * 2.pow(e)

}

var ps = "0000110111011101"

System.print(posit16_decode.call(ps))</syntaxhighlight>

System.print(posit16_decode.call(ps, 3))</syntaxhighlight>