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import defaultSource from "./defaultSource.js";
import beta from "./beta.js";
import geometric from "./geometric.js";
export default (function sourceRandomBinomial(source) {
var G = geometric.source(source),
B = beta.source(source);
function randomBinomial(n, p) {
n = +n;
if ((p = +p) >= 1) return () => n;
if (p <= 0) return () => 0;
return function() {
var acc = 0, nn = n, pp = p;
while (nn * pp > 16 && nn * (1 - pp) > 16) {
var i = Math.floor((nn + 1) * pp),
y = B(i, nn - i + 1)();
if (y <= pp) {
acc += i;
nn -= i;
pp = (pp - y) / (1 - y);
} else {
nn = i - 1;
pp /= y;
}
}
var sign = pp < 0.5,
pFinal = sign ? pp : 1 - pp,
g = G(pFinal);
for (var s = g(), k = 0; s <= nn; ++k) s += g();
return acc + (sign ? k : nn - k);
};
}
randomBinomial.source = sourceRandomBinomial;
return randomBinomial;
})(defaultSource);
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