mirror of
https://github.com/pezkuwichain/pezkuwi-common.git
synced 2026-04-28 06:17:56 +00:00
chore: update to version 14.0.11 and align website URLs
This commit is contained in:
@@ -0,0 +1,41 @@
|
||||
"use strict";
|
||||
Object.defineProperty(exports, "__esModule", { value: true });
|
||||
exports.bnSqrt = bnSqrt;
|
||||
const bn_js_1 = require("./bn.js");
|
||||
const consts_js_1 = require("./consts.js");
|
||||
const toBn_js_1 = require("./toBn.js");
|
||||
/**
|
||||
* @name bnSqrt
|
||||
* @summary Calculates the integer square root of a BN
|
||||
* @example
|
||||
* <BR>
|
||||
*
|
||||
* ```javascript
|
||||
* import BN from 'bn.js';
|
||||
* import { bnSqrt } from '@pezkuwi/util';
|
||||
*
|
||||
* bnSqrt(new BN(16)).toString(); // => '4'
|
||||
* ```
|
||||
*/
|
||||
function bnSqrt(value) {
|
||||
const n = (0, toBn_js_1.bnToBn)(value);
|
||||
if (n.isNeg()) {
|
||||
throw new Error('square root of negative numbers is not supported');
|
||||
}
|
||||
// https://stackoverflow.com/questions/53683995/javascript-big-integer-square-root/
|
||||
// shortcut <= 2^53 - 1 to use the JS utils
|
||||
if (n.lte(consts_js_1.BN_MAX_INTEGER)) {
|
||||
// ~~ More performant version of Math.floor
|
||||
return new bn_js_1.BN(~~Math.sqrt(n.toNumber()));
|
||||
}
|
||||
// Use sqrt(MAX_SAFE_INTEGER) as starting point. since we already know the
|
||||
// output will be larger than this, we expect this to be a safe start
|
||||
let x0 = consts_js_1.BN_SQRT_MAX_INTEGER.clone();
|
||||
while (true) {
|
||||
const x1 = n.div(x0).iadd(x0).ishrn(1);
|
||||
if (x0.eq(x1) || x0.eq(x1.sub(consts_js_1.BN_ONE))) {
|
||||
return x0;
|
||||
}
|
||||
x0 = x1;
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user