aboutsummaryrefslogblamecommitdiffstats
path: root/vendor/brick/math/src/BigNumber.php
blob: 59fcc7ce573f298e304e26484ee11588758fc186 (plain) (tree)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566





















































































































































































































































































































































































































































































































































































                                                                                                                       
<?php

declare(strict_types=1);

namespace Brick\Math;

use Brick\Math\Exception\DivisionByZeroException;
use Brick\Math\Exception\MathException;
use Brick\Math\Exception\NumberFormatException;
use Brick\Math\Exception\RoundingNecessaryException;

/**
 * Common interface for arbitrary-precision rational numbers.
 *
 * @psalm-immutable
 */
abstract class BigNumber implements \Serializable, \JsonSerializable
{
    /**
     * The regular expression used to parse integer, decimal and rational numbers.
     */
    private const PARSE_REGEXP =
        '/^' .
            '(?<sign>[\-\+])?' .
            '(?:' .
                '(?:' .
                    '(?<integral>[0-9]+)?' .
                    '(?<point>\.)?' .
                    '(?<fractional>[0-9]+)?' .
                    '(?:[eE](?<exponent>[\-\+]?[0-9]+))?' .
                ')|(?:' .
                    '(?<numerator>[0-9]+)' .
                    '\/?' .
                    '(?<denominator>[0-9]+)' .
                ')' .
            ')' .
        '$/';

    /**
     * Creates a BigNumber of the given value.
     *
     * The concrete return type is dependent on the given value, with the following rules:
     *
     * - BigNumber instances are returned as is
     * - integer numbers are returned as BigInteger
     * - floating point numbers are converted to a string then parsed as such
     * - strings containing a `/` character are returned as BigRational
     * - strings containing a `.` character or using an exponential notation are returned as BigDecimal
     * - strings containing only digits with an optional leading `+` or `-` sign are returned as BigInteger
     *
     * @param BigNumber|int|float|string $value
     *
     * @return BigNumber
     *
     * @throws NumberFormatException   If the format of the number is not valid.
     * @throws DivisionByZeroException If the value represents a rational number with a denominator of zero.
     *
     * @psalm-pure
     */
    public static function of($value) : BigNumber
    {
        if ($value instanceof BigNumber) {
            return $value;
        }

        if (\is_int($value)) {
            return new BigInteger((string) $value);
        }

        if (\is_float($value)) {
            $value = self::floatToString($value);
        } else {
            $value = (string) $value;
        }

        $throw = function() use ($value) : void {
            throw new NumberFormatException(\sprintf(
                'The given value "%s" does not represent a valid number.',
                $value
            ));
        };

        if (\preg_match(self::PARSE_REGEXP, $value, $matches) !== 1) {
            $throw();
        }

        $getMatch = function(string $value) use ($matches) : ?string {
            return isset($matches[$value]) && $matches[$value] !== '' ? $matches[$value] : null;
        };

        $sign        = $getMatch('sign');
        $numerator   = $getMatch('numerator');
        $denominator = $getMatch('denominator');

        if ($numerator !== null) {
            $numerator   = self::cleanUp($sign . $numerator);
            $denominator = self::cleanUp($denominator);

            if ($denominator === '0') {
                throw DivisionByZeroException::denominatorMustNotBeZero();
            }

            return new BigRational(
                new BigInteger($numerator),
                new BigInteger($denominator),
                false
            );
        }

        $point      = $getMatch('point');
        $integral   = $getMatch('integral');
        $fractional = $getMatch('fractional');
        $exponent   = $getMatch('exponent');

        if ($integral === null && $fractional === null) {
            $throw();
        }

        if ($integral === null) {
            $integral = '0';
        }

        if ($point !== null || $exponent !== null) {
            $fractional = $fractional ?? '';
            $exponent = $exponent !== null ? (int) $exponent : 0;

            if ($exponent === PHP_INT_MIN || $exponent === PHP_INT_MAX) {
                throw new NumberFormatException('Exponent too large.');
            }

            $unscaledValue = self::cleanUp($sign . $integral . $fractional);

            $scale = \strlen($fractional) - $exponent;

            if ($scale < 0) {
                if ($unscaledValue !== '0') {
                    $unscaledValue .= \str_repeat('0', - $scale);
                }
                $scale = 0;
            }

            return new BigDecimal($unscaledValue, $scale);
        }

        $integral = self::cleanUp($sign . $integral);

        return new BigInteger($integral);
    }

    /**
     * Safely converts float to string, avoiding locale-dependent issues.
     *
     * @see https://github.com/brick/math/pull/20
     *
     * @param float $float
     *
     * @return string
     *
     * @psalm-pure
     * @psalm-suppress ImpureFunctionCall
     */
    private static function floatToString(float $float) : string
    {
        $currentLocale = \setlocale(LC_NUMERIC, '0');
        \setlocale(LC_NUMERIC, 'C');

        $result = (string) $float;

        \setlocale(LC_NUMERIC, $currentLocale);

        return $result;
    }

    /**
     * Proxy method to access protected constructors from sibling classes.
     *
     * @internal
     *
     * @param mixed ...$args The arguments to the constructor.
     *
     * @return static
     *
     * @psalm-pure
     */
    protected static function create(... $args) : BigNumber
    {
        /** @psalm-suppress TooManyArguments */
        return new static(... $args);
    }

    /**
     * Returns the minimum of the given values.
     *
     * @param BigNumber|int|float|string ...$values The numbers to compare. All the numbers need to be convertible
     *                                              to an instance of the class this method is called on.
     *
     * @return static The minimum value.
     *
     * @throws \InvalidArgumentException If no values are given.
     * @throws MathException             If an argument is not valid.
     *
     * @psalm-pure
     */
    public static function min(...$values) : BigNumber
    {
        $min = null;

        foreach ($values as $value) {
            $value = static::of($value);

            if ($min === null || $value->isLessThan($min)) {
                $min = $value;
            }
        }

        if ($min === null) {
            throw new \InvalidArgumentException(__METHOD__ . '() expects at least one value.');
        }

        return $min;
    }

    /**
     * Returns the maximum of the given values.
     *
     * @param BigNumber|int|float|string ...$values The numbers to compare. All the numbers need to be convertible
     *                                              to an instance of the class this method is called on.
     *
     * @return static The maximum value.
     *
     * @throws \InvalidArgumentException If no values are given.
     * @throws MathException             If an argument is not valid.
     *
     * @psalm-pure
     */
    public static function max(...$values) : BigNumber
    {
        $max = null;

        foreach ($values as $value) {
            $value = static::of($value);

            if ($max === null || $value->isGreaterThan($max)) {
                $max = $value;
            }
        }

        if ($max === null) {
            throw new \InvalidArgumentException(__METHOD__ . '() expects at least one value.');
        }

        return $max;
    }

    /**
     * Returns the sum of the given values.
     *
     * @param BigNumber|int|float|string ...$values The numbers to add. All the numbers need to be convertible
     *                                              to an instance of the class this method is called on.
     *
     * @return static The sum.
     *
     * @throws \InvalidArgumentException If no values are given.
     * @throws MathException             If an argument is not valid.
     *
     * @psalm-pure
     */
    public static function sum(...$values) : BigNumber
    {
        /** @var BigNumber|null $sum */
        $sum = null;

        foreach ($values as $value) {
            $value = static::of($value);

            if ($sum === null) {
                $sum = $value;
            } else {
                $sum = self::add($sum, $value);
            }
        }

        if ($sum === null) {
            throw new \InvalidArgumentException(__METHOD__ . '() expects at least one value.');
        }

        return $sum;
    }

    /**
     * Adds two BigNumber instances in the correct order to avoid a RoundingNecessaryException.
     *
     * @todo This could be better resolved by creating an abstract protected method in BigNumber, and leaving to
     *       concrete classes the responsibility to perform the addition themselves or delegate it to the given number,
     *       depending on their ability to perform the operation. This will also require a version bump because we're
     *       potentially breaking custom BigNumber implementations (if any...)
     *
     * @param BigNumber $a
     * @param BigNumber $b
     *
     * @return BigNumber
     *
     * @psalm-pure
     */
    private static function add(BigNumber $a, BigNumber $b) : BigNumber
    {
        if ($a instanceof BigRational) {
            return $a->plus($b);
        }

        if ($b instanceof BigRational) {
            return $b->plus($a);
        }

        if ($a instanceof BigDecimal) {
            return $a->plus($b);
        }

        if ($b instanceof BigDecimal) {
            return $b->plus($a);
        }

        /** @var BigInteger $a */

        return $a->plus($b);
    }

    /**
     * Removes optional leading zeros and + sign from the given number.
     *
     * @param string $number The number, validated as a non-empty string of digits with optional leading sign.
     *
     * @return string
     *
     * @psalm-pure
     */
    private static function cleanUp(string $number) : string
    {
        $firstChar = $number[0];

        if ($firstChar === '+' || $firstChar === '-') {
            $number = \substr($number, 1);
        }

        $number = \ltrim($number, '0');

        if ($number === '') {
            return '0';
        }

        if ($firstChar === '-') {
            return '-' . $number;
        }

        return $number;
    }

    /**
     * Checks if this number is equal to the given one.
     *
     * @param BigNumber|int|float|string $that
     *
     * @return bool
     */
    public function isEqualTo($that) : bool
    {
        return $this->compareTo($that) === 0;
    }

    /**
     * Checks if this number is strictly lower than the given one.
     *
     * @param BigNumber|int|float|string $that
     *
     * @return bool
     */
    public function isLessThan($that) : bool
    {
        return $this->compareTo($that) < 0;
    }

    /**
     * Checks if this number is lower than or equal to the given one.
     *
     * @param BigNumber|int|float|string $that
     *
     * @return bool
     */
    public function isLessThanOrEqualTo($that) : bool
    {
        return $this->compareTo($that) <= 0;
    }

    /**
     * Checks if this number is strictly greater than the given one.
     *
     * @param BigNumber|int|float|string $that
     *
     * @return bool
     */
    public function isGreaterThan($that) : bool
    {
        return $this->compareTo($that) > 0;
    }

    /**
     * Checks if this number is greater than or equal to the given one.
     *
     * @param BigNumber|int|float|string $that
     *
     * @return bool
     */
    public function isGreaterThanOrEqualTo($that) : bool
    {
        return $this->compareTo($that) >= 0;
    }

    /**
     * Checks if this number equals zero.
     *
     * @return bool
     */
    public function isZero() : bool
    {
        return $this->getSign() === 0;
    }

    /**
     * Checks if this number is strictly negative.
     *
     * @return bool
     */
    public function isNegative() : bool
    {
        return $this->getSign() < 0;
    }

    /**
     * Checks if this number is negative or zero.
     *
     * @return bool
     */
    public function isNegativeOrZero() : bool
    {
        return $this->getSign() <= 0;
    }

    /**
     * Checks if this number is strictly positive.
     *
     * @return bool
     */
    public function isPositive() : bool
    {
        return $this->getSign() > 0;
    }

    /**
     * Checks if this number is positive or zero.
     *
     * @return bool
     */
    public function isPositiveOrZero() : bool
    {
        return $this->getSign() >= 0;
    }

    /**
     * Returns the sign of this number.
     *
     * @return int -1 if the number is negative, 0 if zero, 1 if positive.
     */
    abstract public function getSign() : int;

    /**
     * Compares this number to the given one.
     *
     * @param BigNumber|int|float|string $that
     *
     * @return int [-1,0,1] If `$this` is lower than, equal to, or greater than `$that`.
     *
     * @throws MathException If the number is not valid.
     */
    abstract public function compareTo($that) : int;

    /**
     * Converts this number to a BigInteger.
     *
     * @return BigInteger The converted number.
     *
     * @throws RoundingNecessaryException If this number cannot be converted to a BigInteger without rounding.
     */
    abstract public function toBigInteger() : BigInteger;

    /**
     * Converts this number to a BigDecimal.
     *
     * @return BigDecimal The converted number.
     *
     * @throws RoundingNecessaryException If this number cannot be converted to a BigDecimal without rounding.
     */
    abstract public function toBigDecimal() : BigDecimal;

    /**
     * Converts this number to a BigRational.
     *
     * @return BigRational The converted number.
     */
    abstract public function toBigRational() : BigRational;

    /**
     * Converts this number to a BigDecimal with the given scale, using rounding if necessary.
     *
     * @param int $scale        The scale of the resulting `BigDecimal`.
     * @param int $roundingMode A `RoundingMode` constant.
     *
     * @return BigDecimal
     *
     * @throws RoundingNecessaryException If this number cannot be converted to the given scale without rounding.
     *                                    This only applies when RoundingMode::UNNECESSARY is used.
     */
    abstract public function toScale(int $scale, int $roundingMode = RoundingMode::UNNECESSARY) : BigDecimal;

    /**
     * Returns the exact value of this number as a native integer.
     *
     * If this number cannot be converted to a native integer without losing precision, an exception is thrown.
     * Note that the acceptable range for an integer depends on the platform and differs for 32-bit and 64-bit.
     *
     * @return int The converted value.
     *
     * @throws MathException If this number cannot be exactly converted to a native integer.
     */
    abstract public function toInt() : int;

    /**
     * Returns an approximation of this number as a floating-point value.
     *
     * Note that this method can discard information as the precision of a floating-point value
     * is inherently limited.
     *
     * If the number is greater than the largest representable floating point number, positive infinity is returned.
     * If the number is less than the smallest representable floating point number, negative infinity is returned.
     *
     * @return float The converted value.
     */
    abstract public function toFloat() : float;

    /**
     * Returns a string representation of this number.
     *
     * The output of this method can be parsed by the `of()` factory method;
     * this will yield an object equal to this one, without any information loss.
     *
     * @return string
     */
    abstract public function __toString() : string;

    /**
     * {@inheritdoc}
     */
    public function jsonSerialize() : string
    {
        return $this->__toString();
    }
}