simple-squiggle

A restricted subset of Squiggle
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bellNumbers.js (1565B)

      1 "use strict";
      2 
      3 Object.defineProperty(exports, "__esModule", {
      4   value: true
      5 });
      6 exports.createBellNumbers = void 0;
      7 
      8 var _factory = require("../../utils/factory.js");
      9 
     10 var name = 'bellNumbers';
     11 var dependencies = ['typed', 'addScalar', 'isNegative', 'isInteger', 'stirlingS2'];
     12 var createBellNumbers = /* #__PURE__ */(0, _factory.factory)(name, dependencies, function (_ref) {
     13   var typed = _ref.typed,
     14       addScalar = _ref.addScalar,
     15       isNegative = _ref.isNegative,
     16       isInteger = _ref.isInteger,
     17       stirlingS2 = _ref.stirlingS2;
     18 
     19   /**
     20    * The Bell Numbers count the number of partitions of a set. A partition is a pairwise disjoint subset of S whose union is S.
     21    * bellNumbers only takes integer arguments.
     22    * The following condition must be enforced: n >= 0
     23    *
     24    * Syntax:
     25    *
     26    *   math.bellNumbers(n)
     27    *
     28    * Examples:
     29    *
     30    *    math.bellNumbers(3) // returns 5
     31    *    math.bellNumbers(8) // returns 4140
     32    *
     33    * See also:
     34    *
     35    *    stirlingS2
     36    *
     37    * @param {Number | BigNumber} n    Total number of objects in the set
     38    * @return {Number | BigNumber}     B(n)
     39    */
     40   return typed(name, {
     41     'number | BigNumber': function numberBigNumber(n) {
     42       if (!isInteger(n) || isNegative(n)) {
     43         throw new TypeError('Non-negative integer value expected in function bellNumbers');
     44       } // Sum (k=0, n) S(n,k).
     45 
     46 
     47       var result = 0;
     48 
     49       for (var i = 0; i <= n; i++) {
     50         result = addScalar(result, stirlingS2(n, i));
     51       }
     52 
     53       return result;
     54     }
     55   });
     56 });
     57 exports.createBellNumbers = createBellNumbers;