simple-squiggle

A restricted subset of Squiggle
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setPowerset.js (2340B)

      1 "use strict";
      2 
      3 Object.defineProperty(exports, "__esModule", {
      4   value: true
      5 });
      6 exports.createSetPowerset = void 0;
      7 
      8 var _array = require("../../utils/array.js");
      9 
     10 var _factory = require("../../utils/factory.js");
     11 
     12 var name = 'setPowerset';
     13 var dependencies = ['typed', 'size', 'subset', 'compareNatural', 'Index'];
     14 var createSetPowerset = /* #__PURE__ */(0, _factory.factory)(name, dependencies, function (_ref) {
     15   var typed = _ref.typed,
     16       size = _ref.size,
     17       subset = _ref.subset,
     18       compareNatural = _ref.compareNatural,
     19       Index = _ref.Index;
     20 
     21   /**
     22    * Create the powerset of a (multi)set. (The powerset contains very possible subsets of a (multi)set.)
     23    * A multi-dimension array will be converted to a single-dimension array before the operation.
     24    *
     25    * Syntax:
     26    *
     27    *    math.setPowerset(set)
     28    *
     29    * Examples:
     30    *
     31    *    math.setPowerset([1, 2, 3])        // returns [[], [1], [2], [3], [1, 2], [1, 3], [2, 3], [1, 2, 3]]
     32    *
     33    * See also:
     34    *
     35    *    setCartesian
     36    *
     37    * @param {Array | Matrix}    a  A (multi)set
     38    * @return {Array}    The powerset of the (multi)set
     39    */
     40   return typed(name, {
     41     'Array | Matrix': function ArrayMatrix(a) {
     42       if (subset(size(a), new Index(0)) === 0) {
     43         // if empty, return empty
     44         return [];
     45       }
     46 
     47       var b = (0, _array.flatten)(Array.isArray(a) ? a : a.toArray()).sort(compareNatural);
     48       var result = [];
     49       var number = 0;
     50 
     51       while (number.toString(2).length <= b.length) {
     52         result.push(_subset(b, number.toString(2).split('').reverse()));
     53         number++;
     54       } // can not return a matrix, because of the different size of the subarrays
     55 
     56 
     57       return _sort(result);
     58     }
     59   }); // create subset
     60 
     61   function _subset(array, bitarray) {
     62     var result = [];
     63 
     64     for (var i = 0; i < bitarray.length; i++) {
     65       if (bitarray[i] === '1') {
     66         result.push(array[i]);
     67       }
     68     }
     69 
     70     return result;
     71   } // sort subsests by length
     72 
     73 
     74   function _sort(array) {
     75     var temp = [];
     76 
     77     for (var i = array.length - 1; i > 0; i--) {
     78       for (var j = 0; j < i; j++) {
     79         if (array[j].length > array[j + 1].length) {
     80           temp = array[j];
     81           array[j] = array[j + 1];
     82           array[j + 1] = temp;
     83         }
     84       }
     85     }
     86 
     87     return array;
     88   }
     89 });
     90 exports.createSetPowerset = createSetPowerset;