simple-squiggle

A restricted subset of Squiggle
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setDifference.js (2418B)

      1 import { flatten, generalize, identify } from '../../utils/array.js';
      2 import { factory } from '../../utils/factory.js';
      3 var name = 'setDifference';
      4 var dependencies = ['typed', 'size', 'subset', 'compareNatural', 'Index', 'DenseMatrix'];
      5 export var createSetDifference = /* #__PURE__ */factory(name, dependencies, _ref => {
      6   var {
      7     typed,
      8     size,
      9     subset,
     10     compareNatural,
     11     Index,
     12     DenseMatrix
     13   } = _ref;
     14 
     15   /**
     16    * Create the difference of two (multi)sets: every element of set1, that is not the element of set2.
     17    * Multi-dimension arrays will be converted to single-dimension arrays before the operation.
     18    *
     19    * Syntax:
     20    *
     21    *    math.setDifference(set1, set2)
     22    *
     23    * Examples:
     24    *
     25    *    math.setDifference([1, 2, 3, 4], [3, 4, 5, 6])            // returns [1, 2]
     26    *    math.setDifference([[1, 2], [3, 4]], [[3, 4], [5, 6]])    // returns [1, 2]
     27    *
     28    * See also:
     29    *
     30    *    setUnion, setIntersect, setSymDifference
     31    *
     32    * @param {Array | Matrix}    a1  A (multi)set
     33    * @param {Array | Matrix}    a2  A (multi)set
     34    * @return {Array | Matrix}    The difference of two (multi)sets
     35    */
     36   return typed(name, {
     37     'Array | Matrix, Array | Matrix': function ArrayMatrixArrayMatrix(a1, a2) {
     38       var result;
     39 
     40       if (subset(size(a1), new Index(0)) === 0) {
     41         // empty-anything=empty
     42         result = [];
     43       } else if (subset(size(a2), new Index(0)) === 0) {
     44         // anything-empty=anything
     45         return flatten(a1.toArray());
     46       } else {
     47         var b1 = identify(flatten(Array.isArray(a1) ? a1 : a1.toArray()).sort(compareNatural));
     48         var b2 = identify(flatten(Array.isArray(a2) ? a2 : a2.toArray()).sort(compareNatural));
     49         result = [];
     50         var inb2;
     51 
     52         for (var i = 0; i < b1.length; i++) {
     53           inb2 = false;
     54 
     55           for (var j = 0; j < b2.length; j++) {
     56             if (compareNatural(b1[i].value, b2[j].value) === 0 && b1[i].identifier === b2[j].identifier) {
     57               // the identifier is always a decimal int
     58               inb2 = true;
     59               break;
     60             }
     61           }
     62 
     63           if (!inb2) {
     64             result.push(b1[i]);
     65           }
     66         }
     67       } // return an array, if both inputs were arrays
     68 
     69 
     70       if (Array.isArray(a1) && Array.isArray(a2)) {
     71         return generalize(result);
     72       } // return a matrix otherwise
     73 
     74 
     75       return new DenseMatrix(generalize(result));
     76     }
     77   });
     78 });