simple-squiggle

A restricted subset of Squiggle
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sqrt.js (1995B)

      1 import { factory } from '../../utils/factory.js';
      2 import { deepMap } from '../../utils/collection.js';
      3 var name = 'sqrt';
      4 var dependencies = ['config', 'typed', 'Complex'];
      5 export var createSqrt = /* #__PURE__ */factory(name, dependencies, _ref => {
      6   var {
      7     config,
      8     typed,
      9     Complex
     10   } = _ref;
     11 
     12   /**
     13    * Calculate the square root of a value.
     14    *
     15    * For matrices, the function is evaluated element wise.
     16    *
     17    * Syntax:
     18    *
     19    *    math.sqrt(x)
     20    *
     21    * Examples:
     22    *
     23    *    math.sqrt(25)                // returns 5
     24    *    math.square(5)               // returns 25
     25    *    math.sqrt(-4)                // returns Complex 2i
     26    *
     27    * See also:
     28    *
     29    *    square, multiply, cube, cbrt, sqrtm
     30    *
     31    * @param {number | BigNumber | Complex | Array | Matrix | Unit} x
     32    *            Value for which to calculate the square root.
     33    * @return {number | BigNumber | Complex | Array | Matrix | Unit}
     34    *            Returns the square root of `x`
     35    */
     36   return typed('sqrt', {
     37     number: _sqrtNumber,
     38     Complex: function Complex(x) {
     39       return x.sqrt();
     40     },
     41     BigNumber: function BigNumber(x) {
     42       if (!x.isNegative() || config.predictable) {
     43         return x.sqrt();
     44       } else {
     45         // negative value -> downgrade to number to do complex value computation
     46         return _sqrtNumber(x.toNumber());
     47       }
     48     },
     49     'Array | Matrix': function ArrayMatrix(x) {
     50       // deep map collection, skip zeros since sqrt(0) = 0
     51       return deepMap(x, this, true);
     52     },
     53     Unit: function Unit(x) {
     54       // Someday will work for complex units when they are implemented
     55       return x.pow(0.5);
     56     }
     57   });
     58   /**
     59    * Calculate sqrt for a number
     60    * @param {number} x
     61    * @returns {number | Complex} Returns the square root of x
     62    * @private
     63    */
     64 
     65   function _sqrtNumber(x) {
     66     if (isNaN(x)) {
     67       return NaN;
     68     } else if (x >= 0 || config.predictable) {
     69       return Math.sqrt(x);
     70     } else {
     71       return new Complex(x, 0).sqrt();
     72     }
     73   }
     74 });