1 | 'use strict';
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2 | var $ = require('../internals/export');
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3 | var uncurryThis = require('../internals/function-uncurry-this');
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4 | var toIntegerOrInfinity = require('../internals/to-integer-or-infinity');
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5 | var thisNumberValue = require('../internals/this-number-value');
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6 | var $repeat = require('../internals/string-repeat');
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7 | var fails = require('../internals/fails');
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8 |
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9 | var $RangeError = RangeError;
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10 | var $String = String;
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11 | var floor = Math.floor;
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12 | var repeat = uncurryThis($repeat);
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13 | var stringSlice = uncurryThis(''.slice);
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14 | var nativeToFixed = uncurryThis(1.0.toFixed);
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15 |
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16 | var pow = function (x, n, acc) {
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17 | return n === 0 ? acc : n % 2 === 1 ? pow(x, n - 1, acc * x) : pow(x * x, n / 2, acc);
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18 | };
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19 |
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20 | var log = function (x) {
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21 | var n = 0;
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22 | var x2 = x;
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23 | while (x2 >= 4096) {
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24 | n += 12;
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25 | x2 /= 4096;
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26 | }
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27 | while (x2 >= 2) {
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28 | n += 1;
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29 | x2 /= 2;
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30 | } return n;
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31 | };
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32 |
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33 | var multiply = function (data, n, c) {
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34 | var index = -1;
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35 | var c2 = c;
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36 | while (++index < 6) {
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37 | c2 += n * data[index];
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38 | data[index] = c2 % 1e7;
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39 | c2 = floor(c2 / 1e7);
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40 | }
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41 | };
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42 |
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43 | var divide = function (data, n) {
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44 | var index = 6;
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45 | var c = 0;
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46 | while (--index >= 0) {
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47 | c += data[index];
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48 | data[index] = floor(c / n);
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49 | c = (c % n) * 1e7;
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50 | }
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51 | };
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52 |
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53 | var dataToString = function (data) {
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54 | var index = 6;
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55 | var s = '';
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56 | while (--index >= 0) {
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57 | if (s !== '' || index === 0 || data[index] !== 0) {
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58 | var t = $String(data[index]);
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59 | s = s === '' ? t : s + repeat('0', 7 - t.length) + t;
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60 | }
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61 | } return s;
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62 | };
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63 |
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64 | var FORCED = fails(function () {
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65 | return nativeToFixed(0.00008, 3) !== '0.000' ||
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66 | nativeToFixed(0.9, 0) !== '1' ||
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67 | nativeToFixed(1.255, 2) !== '1.25' ||
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68 | nativeToFixed(1000000000000000128.0, 0) !== '1000000000000000128';
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69 | }) || !fails(function () {
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70 |
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71 | nativeToFixed({});
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72 | });
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73 |
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74 |
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75 |
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76 | $({ target: 'Number', proto: true, forced: FORCED }, {
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77 | toFixed: function toFixed(fractionDigits) {
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78 | var number = thisNumberValue(this);
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79 | var fractDigits = toIntegerOrInfinity(fractionDigits);
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80 | var data = [0, 0, 0, 0, 0, 0];
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81 | var sign = '';
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82 | var result = '0';
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83 | var e, z, j, k;
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84 |
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85 |
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86 | if (fractDigits < 0 || fractDigits > 20) throw new $RangeError('Incorrect fraction digits');
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87 |
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88 | if (number !== number) return 'NaN';
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89 | if (number <= -1e21 || number >= 1e21) return $String(number);
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90 | if (number < 0) {
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91 | sign = '-';
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92 | number = -number;
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93 | }
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94 | if (number > 1e-21) {
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95 | e = log(number * pow(2, 69, 1)) - 69;
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96 | z = e < 0 ? number * pow(2, -e, 1) : number / pow(2, e, 1);
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97 | z *= 0x10000000000000;
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98 | e = 52 - e;
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99 | if (e > 0) {
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100 | multiply(data, 0, z);
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101 | j = fractDigits;
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102 | while (j >= 7) {
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103 | multiply(data, 1e7, 0);
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104 | j -= 7;
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105 | }
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106 | multiply(data, pow(10, j, 1), 0);
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107 | j = e - 1;
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108 | while (j >= 23) {
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109 | divide(data, 1 << 23);
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110 | j -= 23;
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111 | }
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112 | divide(data, 1 << j);
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113 | multiply(data, 1, 1);
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114 | divide(data, 2);
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115 | result = dataToString(data);
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116 | } else {
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117 | multiply(data, 0, z);
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118 | multiply(data, 1 << -e, 0);
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119 | result = dataToString(data) + repeat('0', fractDigits);
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120 | }
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121 | }
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122 | if (fractDigits > 0) {
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123 | k = result.length;
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124 | result = sign + (k <= fractDigits
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125 | ? '0.' + repeat('0', fractDigits - k) + result
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126 | : stringSlice(result, 0, k - fractDigits) + '.' + stringSlice(result, k - fractDigits));
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127 | } else {
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128 | result = sign + result;
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129 | } return result;
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130 | }
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131 | });
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