simple-squiggle

A restricted subset of Squiggle
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bellNumbers.js (1311B)

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