simple-squiggle

A restricted subset of Squiggle
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diff.js (5868B)


      1 "use strict";
      2 
      3 Object.defineProperty(exports, "__esModule", {
      4   value: true
      5 });
      6 exports.createDiff = void 0;
      7 
      8 var _factory = require("../../utils/factory.js");
      9 
     10 var _number = require("../../utils/number.js");
     11 
     12 var _is = require("../../utils/is.js");
     13 
     14 var name = 'diff';
     15 var dependencies = ['typed', 'matrix', 'subtract', 'number'];
     16 var createDiff = /* #__PURE__ */(0, _factory.factory)(name, dependencies, function (_ref) {
     17   var typed = _ref.typed,
     18       matrix = _ref.matrix,
     19       subtract = _ref.subtract,
     20       number = _ref.number;
     21 
     22   /**
     23    * Create a new matrix or array of the difference between elements of the given array
     24    * The optional dim parameter lets you specify the dimension to evaluate the difference of
     25    * If no dimension parameter is passed it is assumed as dimension 0
     26    *
     27    * Dimension is zero-based in javascript and one-based in the parser and can be a number or bignumber
     28    * Arrays must be 'rectangular' meaning arrays like [1, 2]
     29    * If something is passed as a matrix it will be returned as a matrix but other than that all matrices are converted to arrays
     30    *
     31    * Syntax:
     32    *
     33    *     math.diff(arr)
     34    *     math.diff(arr, dim)
     35    *
     36    * Examples:
     37    *
     38    *     const arr = [1, 2, 4, 7, 0]
     39    *     math.diff(arr) // returns [1, 2, 3, -7] (no dimension passed so 0 is assumed)
     40    *     math.diff(math.matrix(arr)) // returns math.matrix([1, 2, 3, -7])
     41    *
     42    *     const arr = [[1, 2, 3, 4, 5], [1, 2, 3, 4, 5], [9, 8, 7, 6, 4]]
     43    *     math.diff(arr) // returns [[0, 0, 0, 0, 0], [8, 6, 4, 2, -1]]
     44    *     math.diff(arr, 0) // returns [[0, 0, 0, 0, 0], [8, 6, 4, 2, -1]]
     45    *     math.diff(arr, 1) // returns [[1, 1, 1, 1], [1, 1, 1, 1], [-1, -1, -1, -2]]
     46    *     math.diff(arr, math.bignumber(1)) // returns [[1, 1, 1, 1], [1, 1, 1, 1], [-1, -1, -1, -2]]
     47    *
     48    *     math.diff(arr, 2) // throws RangeError as arr is 2 dimensional not 3
     49    *     math.diff(arr, -1) // throws RangeError as negative dimensions are not allowed
     50    *
     51    *     // These will all produce the same result
     52    *     math.diff([[1, 2], [3, 4]])
     53    *     math.diff([math.matrix([1, 2]), math.matrix([3, 4])])
     54    *     math.diff([[1, 2], math.matrix([3, 4])])
     55    *     math.diff([math.matrix([1, 2]), [3, 4]])
     56    *     // They do not produce the same result as  math.diff(math.matrix([[1, 2], [3, 4]])) as this returns a matrix
     57    *
     58    * See Also:
     59    *
     60    *      sum
     61    *      subtract
     62    *      partitionSelect
     63    *
     64    * @param {Array | Matrix} arr    An array or matrix
     65    * @param {number} dim            Dimension
     66    * @return {Array | Matrix}       Difference between array elements in given dimension
     67    */
     68   return typed(name, {
     69     'Array | Matrix': function ArrayMatrix(arr) {
     70       // No dimension specified => assume dimension 0
     71       if ((0, _is.isMatrix)(arr)) {
     72         return matrix(_diff(arr.toArray()));
     73       } else {
     74         return _diff(arr);
     75       }
     76     },
     77     'Array | Matrix, number': function ArrayMatrixNumber(arr, dim) {
     78       if (!(0, _number.isInteger)(dim)) throw new RangeError('Dimension must be a whole number');
     79 
     80       if ((0, _is.isMatrix)(arr)) {
     81         return matrix(_recursive(arr.toArray(), dim));
     82       } else {
     83         return _recursive(arr, dim);
     84       }
     85     },
     86     'Array | Matrix, BigNumber': function ArrayMatrixBigNumber(arr, dim) {
     87       return this(arr, number(dim));
     88     }
     89   });
     90   /**
     91    * Recursively find the correct dimension in the array/matrix
     92    * Then Apply _diff to that dimension
     93    *
     94    * @param {Array} arr      The array
     95    * @param {number} dim     Dimension
     96    * @return {Array}         resulting array
     97    */
     98 
     99   function _recursive(arr, dim) {
    100     if ((0, _is.isMatrix)(arr)) {
    101       arr = arr.toArray(); // Makes sure arrays like [ matrix([0, 1]), matrix([1, 0]) ] are processed properly
    102     }
    103 
    104     if (!Array.isArray(arr)) {
    105       throw RangeError('Array/Matrix does not have that many dimensions');
    106     }
    107 
    108     if (dim > 0) {
    109       var result = [];
    110       arr.forEach(function (element) {
    111         result.push(_recursive(element, dim - 1));
    112       });
    113       return result;
    114     } else if (dim === 0) {
    115       return _diff(arr);
    116     } else {
    117       throw RangeError('Cannot have negative dimension');
    118     }
    119   }
    120   /**
    121    * Difference between elements in the array
    122    *
    123    * @param {Array} arr      An array
    124    * @return {Array}         resulting array
    125    */
    126 
    127 
    128   function _diff(arr) {
    129     var result = [];
    130     var size = arr.length;
    131 
    132     if (size < 2) {
    133       return arr;
    134     }
    135 
    136     for (var i = 1; i < size; i++) {
    137       result.push(_ElementDiff(arr[i - 1], arr[i]));
    138     }
    139 
    140     return result;
    141   }
    142   /**
    143    * Difference between 2 objects
    144    *
    145    * @param {Object} obj1    First object
    146    * @param {Object} obj2    Second object
    147    * @return {Array}         resulting array
    148    */
    149 
    150 
    151   function _ElementDiff(obj1, obj2) {
    152     // Convert matrices to arrays
    153     if ((0, _is.isMatrix)(obj1)) obj1 = obj1.toArray();
    154     if ((0, _is.isMatrix)(obj2)) obj2 = obj2.toArray();
    155     var obj1IsArray = Array.isArray(obj1);
    156     var obj2IsArray = Array.isArray(obj2);
    157 
    158     if (obj1IsArray && obj2IsArray) {
    159       return _ArrayDiff(obj1, obj2);
    160     }
    161 
    162     if (!obj1IsArray && !obj2IsArray) {
    163       return subtract(obj2, obj1); // Difference is (second - first) NOT (first - second)
    164     }
    165 
    166     throw TypeError('Cannot calculate difference between 1 array and 1 non-array');
    167   }
    168   /**
    169    * Difference of elements in 2 arrays
    170    *
    171    * @param {Array} arr1     Array 1
    172    * @param {Array} arr2     Array 2
    173    * @return {Array}         resulting array
    174    */
    175 
    176 
    177   function _ArrayDiff(arr1, arr2) {
    178     if (arr1.length !== arr2.length) {
    179       throw RangeError('Not all sub-arrays have the same length');
    180     }
    181 
    182     var result = [];
    183     var size = arr1.length;
    184 
    185     for (var i = 0; i < size; i++) {
    186       result.push(_ElementDiff(arr1[i], arr2[i]));
    187     }
    188 
    189     return result;
    190   }
    191 });
    192 exports.createDiff = createDiff;