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compute = function (precision) {
// Calculate number of digits per iteration
let dpi = Decimal.set({ precision: 100 })("640_320")
.pow(3)
.div(Decimal("1_728" /* = 24 * 6 * 2 * 6 */))
.log();
Decimal.precision = "3.".length + (precision = +precision || 1);
function chudnovsky(n, C) {
// C = 426880 * 10005^0.5
C = Decimal("426_880").times(Decimal("10_005").sqrt());
Object.assign(C, {
"545_140_134": Decimal("545_140_134"),
"-262_537_412_640_768_000": Decimal("-262_537_412_640_768_000")
});
// See https://www.sitepoint.com/javascript-functions-that-define-and-rewrite-themselves/
chudnovsky = function (n, pi, q, Mq, Lq, Xq, Kq) {
for (
q = 0,
pi = Decimal(0),
Kq = Decimal(-6),
Lq = Decimal("13_591_409"),
Mq = Xq = Decimal(1);
q++ < n;
) {
/*!
* Multinomial term: Mq = (6q)! / ((3q)! * (q)!^3)
* Linear term: Lq = 545140134q + 13591409
* Exponential term: Xq = -262537412640768000^q
* Pi series partial summation:
*/
pi = pi.plus(Mq.times(Lq).div(Xq));
Kq = Kq.plus(12);
Mq = Mq.times(Kq.pow(3).minus(Kq.times(16)).div(Decimal(q).pow(3)));
Lq = Lq.plus(C["545_140_134"]);
Xq = Xq.times(C["-262_537_412_640_768_000"]);
}
// π = C / pi
return C.div(pi).valueOf();
};
return chudnovsky(n);
}
let result = [];
for (let n of Array.from(
{ length: Math.max(Math.ceil(precision / +dpi), 1) },
(_, i) => ++i
)) {
result[n - 1] = chudnovsky(n);
}
return result;
}
runAsWorker
.call(
clone(compute, 'importScripts("' + (await require.resolve(library)) + '")'),
1000
)
.then(async function* (result) {
await visibility();
yield* traverse(result, inspect);
})
.catch((failure) => failure)
inspect(decimalPlaces)
decimalPlaces = Decimal.set({ precision: 100 })("640_320")
.pow(3)
.div(Decimal("1_728" /* = 24 * 6 * 2 * 6 */))
.log()
inspect(C)
Decimal.set({ precision: 100 })("640_320").pow(1.5).div(12).equals(C)
C = Decimal.set({ precision: 100 })("426_880").times(Decimal("10_005").sqrt())
545_140_134 === 163 * 127 * 19 * 11 * 7 * 3 ** 2 * 2
13_591_409 === 1_045_493 * 13
Decimal("262_537_412_640_768_000").equals(Decimal("640_320").pow(3))
Decimal.set({ precision: 100 })
// = exp(π * sqrt(163)) - 640320^3
.acos(-1)
.times(Decimal(163).sqrt())
.naturalExponential()
.minus(Decimal("640_320").pow(3))
.toFixed(21)
.slice(0, -1) + "…"
Decimal = require(library)
library = "decimal.js@10.3.1/decimal.js"
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