28 lines
1.2 KiB
D
28 lines
1.2 KiB
D
import std.stdio, std.mathspecial;
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real myGamma(in real x) pure nothrow {
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static immutable real[30] table = [
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1.00000000000000000000, 0.57721566490153286061, -0.65587807152025388108,
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-0.04200263503409523553, 0.16653861138229148950, -0.04219773455554433675,
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-0.00962197152787697356, 0.00721894324666309954, -0.00116516759185906511,
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-0.00021524167411495097, 0.00012805028238811619, -0.00002013485478078824,
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-0.00000125049348214267, 0.00000113302723198170, -0.00000020563384169776,
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0.00000000611609510448, 0.00000000500200764447, -0.00000000118127457049,
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0.00000000010434267117, 0.00000000000778226344, -0.00000000000369680562,
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0.00000000000051003703, -0.00000000000002058326, -0.00000000000000534812,
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0.00000000000000122678, -0.00000000000000011813, 0.00000000000000000119,
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0.00000000000000000141, -0.00000000000000000023, 0.00000000000000000002];
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immutable real y = x - 1.0L;
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real sm = table[$ - 1];
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foreach_reverse (immutable an; table[0 .. $ - 1])
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sm = sm * y + an;
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return 1.0L / sm;
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}
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void main() {
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foreach (immutable i; 1 .. 11) {
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immutable real x = i / 3.0L;
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writefln("%f: %20.19e %20.19e", x, myGamma(x), gamma(x));
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}
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}
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