jiangchengfeiyi-xiaochengxu/node_modules/mathjs/lib/cjs/function/set/setIntersect.js
2025-01-02 11:13:50 +08:00

69 lines
2.3 KiB
JavaScript

"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.createSetIntersect = void 0;
var _array = require("../../utils/array.js");
var _factory = require("../../utils/factory.js");
const name = 'setIntersect';
const dependencies = ['typed', 'size', 'subset', 'compareNatural', 'Index', 'DenseMatrix'];
const createSetIntersect = exports.createSetIntersect = /* #__PURE__ */(0, _factory.factory)(name, dependencies, _ref => {
let {
typed,
size,
subset,
compareNatural,
Index,
DenseMatrix
} = _ref;
/**
* Create the intersection of two (multi)sets.
* Multi-dimension arrays will be converted to single-dimension arrays before the operation.
*
* Syntax:
*
* math.setIntersect(set1, set2)
*
* Examples:
*
* math.setIntersect([1, 2, 3, 4], [3, 4, 5, 6]) // returns [3, 4]
* math.setIntersect([[1, 2], [3, 4]], [[3, 4], [5, 6]]) // returns [3, 4]
*
* See also:
*
* setUnion, setDifference
*
* @param {Array | Matrix} a1 A (multi)set
* @param {Array | Matrix} a2 A (multi)set
* @return {Array | Matrix} The intersection of two (multi)sets
*/
return typed(name, {
'Array | Matrix, Array | Matrix': function (a1, a2) {
let result;
if (subset(size(a1), new Index(0)) === 0 || subset(size(a2), new Index(0)) === 0) {
// of any of them is empty, return empty
result = [];
} else {
const b1 = (0, _array.identify)((0, _array.flatten)(Array.isArray(a1) ? a1 : a1.toArray()).sort(compareNatural));
const b2 = (0, _array.identify)((0, _array.flatten)(Array.isArray(a2) ? a2 : a2.toArray()).sort(compareNatural));
result = [];
for (let i = 0; i < b1.length; i++) {
for (let j = 0; j < b2.length; j++) {
if (compareNatural(b1[i].value, b2[j].value) === 0 && b1[i].identifier === b2[j].identifier) {
// the identifier is always a decimal int
result.push(b1[i]);
break;
}
}
}
}
// return an array, if both inputs were arrays
if (Array.isArray(a1) && Array.isArray(a2)) {
return (0, _array.generalize)(result);
}
// return a matrix otherwise
return new DenseMatrix((0, _array.generalize)(result));
}
});
});