lml-main
Version:
This is now a mono repository published into many standalone packages.
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JavaScript
;
var flatten = require('../../utils/array').flatten;
var identify = require('../../utils/array').identify;
function factory (type, config, load, typed) {
var equal = load(require('../relational/equal'));
var index = load(require('../../type/matrix/MatrixIndex'));
var size = load(require('../matrix/size'));
var subset = load(require('../matrix/subset'));
var compareNatural = load(require('../relational/compareNatural'));
/**
* Check whether a (multi)set is a subset of another (multi)set. (Every element of set1 is the element of set2.)
* Multi-dimension arrays will be converted to single-dimension arrays before the operation.
*
* Syntax:
*
* math.setIsSubset(set1, set2)
*
* Examples:
*
* math.setIsSubset([1, 2], [3, 4, 5, 6]); // returns false
* math.setIsSubset([3, 4], [3, 4, 5, 6]); // returns true
*
* See also:
*
* setUnion, setIntersect, setDifference
*
* @param {Array | Matrix} a1 A (multi)set
* @param {Array | Matrix} a2 A (multi)set
* @return {boolean} true | false
*/
var setIsSubset = typed('setIsSubset', {
'Array | Matrix, Array | Matrix': function (a1, a2) {
if (subset(size(a1), new index(0)) === 0) { // empty is a subset of anything
return true;
}
else if (subset(size(a2), new index(0)) === 0) { // anything is not a subset of empty
return false;
}
var b1 = identify(flatten(Array.isArray(a1) ? a1 : a1.toArray()).sort(compareNatural));
var b2 = identify(flatten(Array.isArray(a2) ? a2 : a2.toArray()).sort(compareNatural));
var inb2;
for (var i=0; i<b1.length; i++) {
inb2 = false;
for (var j=0; j<b2.length; j++) {
if (equal(b1[i].value, b2[j].value) && b1[i].identifier === b2[j].identifier) { // the identifier is always a decimal int
inb2 = true;
break;
}
}
if (inb2 === false) {
return false;
}
}
return true;
}
});
return setIsSubset;
}
exports.name = 'setIsSubset';
exports.factory = factory;