simple-squiggle

A restricted subset of Squiggle
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composition.js (1458B)

      1 import { factory } from '../../utils/factory.js';
      2 var name = 'composition';
      3 var dependencies = ['typed', 'addScalar', 'combinations', 'isNegative', 'isPositive', 'isInteger', 'larger'];
      4 export var createComposition = /* #__PURE__ */factory(name, dependencies, _ref => {
      5   var {
      6     typed,
      7     addScalar,
      8     combinations,
      9     isPositive,
     10     isNegative,
     11     isInteger,
     12     larger
     13   } = _ref;
     14 
     15   /**
     16    * The composition counts of n into k parts.
     17    *
     18    * composition only takes integer arguments.
     19    * The following condition must be enforced: k <= n.
     20    *
     21    * Syntax:
     22    *
     23    *   math.composition(n, k)
     24    *
     25    * Examples:
     26    *
     27    *    math.composition(5, 3) // returns 6
     28    *
     29    * See also:
     30    *
     31    *    combinations
     32    *
     33    * @param {Number | BigNumber} n    Total number of objects in the set
     34    * @param {Number | BigNumber} k    Number of objects in the subset
     35    * @return {Number | BigNumber}     Returns the composition counts of n into k parts.
     36    */
     37   return typed(name, {
     38     'number | BigNumber, number | BigNumber': function numberBigNumberNumberBigNumber(n, k) {
     39       if (!isInteger(n) || !isPositive(n) || !isInteger(k) || !isPositive(k)) {
     40         throw new TypeError('Positive integer value expected in function composition');
     41       } else if (larger(k, n)) {
     42         throw new TypeError('k must be less than or equal to n in function composition');
     43       }
     44 
     45       return combinations(addScalar(n, -1), addScalar(k, -1));
     46     }
     47   });
     48 });