Spl::gamma() - Code Metrics - TheDevNetwork/PhpTypes - Measure and Improve Code Quality continuously with Scrutinizer

Spl::gamma() C
last analyzed 2017-11-18 07:09 UTC

↳ Parent: Spl

Complexity

Conditions	9
Paths	12

Size

Total Lines	75
Code Lines	49

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	31
CRAP Score	9

Importance

Changes

Metric	Value
dl	0
loc	75
ccs	31
cts	31
cp	1
rs	5.875
c	0
b	0
f	0
cc	9
eloc	49
nc	12
nop	1
crap	9

How to fix Long Method

<?php

namespace Tdn\PhpTypes\Math\Library;

use Tdn\PhpTypes\Exception\InvalidNumberException;
use Tdn\PhpTypes\Math\DefaultMathAdapter;
use Tdn\PhpTypes\Type\StringType;

/**
 * Class Spl.
 */
class Spl implements MathLibraryInterface
{
    /**
     * @var int
     */
    private $roundingStrategy;

    /**
     * @param int $roundingStrategy a PHP_ROUND_HALF_* integer
     */
    public function __construct(int $roundingStrategy)
    {
        $this->roundingStrategy = $roundingStrategy;
    }

    /**
     * Add two arbitrary precision numbers.
     *
     * @param string $leftOperand
     * @param string $rightOperand
     * @param int    $precision
     *
     * @return string
     */
    public function add(string $leftOperand, string $rightOperand, int $precision = 0): string
    {
        return (string) ($this->isIntOperation($precision) ? (intval($leftOperand) + intval($rightOperand)) :
            round(floatval($leftOperand) + floatval($rightOperand), $precision, $this->roundingStrategy));
    }

    /**
     * Subtract two arbitrary precision numbers.
     *
     * @param string $leftOperand
     * @param string $rightOperand
     * @param int    $precision
     *
     * @return string
     */
    public function subtract(string $leftOperand, string $rightOperand, int $precision = 0): string
    {
        return (string) ($this->isIntOperation($precision) ? (intval($leftOperand) - intval($rightOperand)) :
            round($leftOperand - $rightOperand, $precision, $this->roundingStrategy));
    }

    /**
     * Multiply two arbitrary precision numbers.
     *
     * @param string $leftOperand
     * @param string $rightOperand
     * @param int    $precision
     *
     * @return string
     */
    public function multiply(string $leftOperand, string $rightOperand, int $precision = 0): string
    {
        return (string) ($this->isIntOperation($precision) ? (intval($leftOperand) * intval($rightOperand)) :
            round($leftOperand * $rightOperand, ($precision ?? 0), $this->roundingStrategy));
    }

    /**
     * Divide two arbitrary precision numbers.
     *
     * @param string $leftOperand
     * @param string $rightOperand
     * @param int    $precision
     *
     * @return string
     */
    public function divide(string $leftOperand, string $rightOperand, int $precision = 0): string
    {
        return (string) ($this->isIntOperation($precision) ? (intval($leftOperand) / intval($rightOperand)) :
            round($leftOperand / $rightOperand, $precision, $this->roundingStrategy));
    }

    /**
     * Compare two arbitrary precision numbers.
     *
     * @param string $leftOperand
     * @param string $rightOperand
     * @param int    $precision
     *
     * @return string
     */
    public function compare(string $leftOperand, string $rightOperand, int $precision = 0): string
    {
        return strval($leftOperand <=> $rightOperand);
    }

    /**
     * Get modulus of an arbitrary precision number.
     *
     * @param string $operand
     * @param string $modulus
     * @param int    $precision
     *
     * @return string
     */
    public function modulus(string $operand, string $modulus, int $precision = 0): string
    {
        return (string) round(
            fmod(
                floatval($operand),
                floatval($modulus)
            ),
            ($precision ?? 0),
            $this->roundingStrategy
        );
    }

    /**
     * Raise an arbitrary precision number to another.
     *
     * @param string $leftOperand
     * @param string $rightOperand
     * @param int    $precision
     *
     * @return string
     */
    public function power(string $leftOperand, string $rightOperand, int $precision = 0): string
    {
        return (string) round(
            pow(
                floatval($leftOperand),
                floatval($rightOperand)
            ),
            ($precision ?? 0),
            $this->roundingStrategy
        );
    }

    /**
     * Get the square root of an arbitrary precision number.
     *
     * @param string $operand
     * @param int    $precision
     *
     * @return string
     */
    public function squareRoot(string $operand, int $precision = 0): string
    {
        return (string) round(sqrt(floatval($operand)), ($precision ?? 0), $this->roundingStrategy);
    }

    /**
     * Returns absolute value of operand.
     *
     * @param string $operand
     *
     * @return string
     */
    public function absolute(string $operand): string
    {
        return (string) abs($operand);
    }

    /**
     * Negates a number. Opposite of absolute/abs.
     *
     * @param string $operand
     *
     * @return string
     */
    public function negate(string $operand): string
    {
        return strval($operand * -1);
    }

    /**
     * Returns the factorial of operand.
     *
     * @param string $operand
     *
     * @return string
     */
    public function factorial(string $operand): string
    {
        if (StringType::create($operand)->contains('.')) {
            ++$operand;

            return $this->gamma((string) $operand);
        }

        $factorial = function (string $num) use (&$factorial) {
            if ($num < 2) {
                return 1;
            }

            return $factorial(strval($num - 1)) * $num;
        };

        return (string) $factorial($operand);
    }

    /**
     * Greatest common divisor.
     *
     * @param string $leftOperand
     * @param string $rightOperand
     *
     * @return string
     */
    public function gcd(string $leftOperand, string $rightOperand): string
    {
        $gcd = function (string $a, string $b) use (&$gcd) {
            return $b ? $gcd($b, strval($a % $b)) : $a;
        };

        $exponent = $this->getSmallestDecimalPlaceCount($leftOperand, $rightOperand);

        return (string) (
            $gcd(
                strval($leftOperand * (pow(10, $exponent))),
                strval($rightOperand * (pow(10, $exponent)))
            ) / pow(10, $exponent)
        );
    }

    /**
     * Calculates to the nth root.
     *
     * @param string $operand
     * @param int    $nth
     *
     * @return string
     */
    public function root(string $operand, int $nth): string
    {
        //Implement something later.
        throw new \RuntimeException('Not a valid library for root^n.');
    }

    /**
     * Gets the next prime after operand.
     *
     * @param string $operand
     *
     * @return string
     */
    public function nextPrime(string $operand): string
    {
        $operand = (intval($operand) + 1);
        for ($i = $operand;; ++$i) {
            if ($this->isPrime(strval($i))) {
                break;
            }
        }

        return (string) $i;
    }

    /**
     * @param string $operand
     * @param int    $reps
     *
     * @return bool
     */
    public function isPrime(string $operand, int $reps = 10): bool
    {
        $x = floor(sqrt(floatval($operand)));
        for ($i = 2; $i <= $x; ++$i) {
            if (($operand % $i) == 0) {
                break;
            }
        }

        return ($x == ($i - 1)) ? true : false;
    }

    /**
     * Checks if operand is perfect square.
     *
     * @param string $operand
     * @param int    $precision
     *
     * @return bool
     */
    public function isPerfectSquare(string $operand, int $precision = 0): bool
    {
        $candidate = $this->squareRoot($operand, $precision + 1);

        return $candidate == intval($candidate);
    }

    /**
     * @return bool
     */
    public function isEnabled(): bool
    {
        return true;
    }

    /**
     * @param string $type
     *
     * @return bool
     */
    public function supportsOperationType(string $type): bool
    {
        // Supports both float and int.
        return true;
    }

    /**
     * @param string $operand
     *
     * @return string
     */
    public function gamma(string $operand): string
    {
        if ($operand <= 0.0) {
            throw new InvalidNumberException('Operand must be a positive number.');
        }

        // Euler's gamma constant
        $gamma = 0.577215664901532860606512090;

        if ($operand < 0.001) {
            return strval(1.0 / ($operand * (1.0 + $gamma * $operand)));
        }

        if ($operand < 12.0) {
            $y = $operand;
            $n = 0;
            $lessThanOne = ($y < 1.0);
            if ($lessThanOne) {
                $y += 1.0;
            } else {
                // will use n later
                $n = floor($y) - 1;
                $y -= $n;
            }

            $p = [
                -1.71618513886549492533811E+0,
                2.47656508055759199108314E+1,
                -3.79804256470945635097577E+2,
                6.29331155312818442661052E+2,
                8.66966202790413211295064E+2,
                -3.14512729688483675254357E+4,
                -3.61444134186911729807069E+4,
                6.64561438202405440627855E+4,
            ];

            $q = [
                -3.08402300119738975254353E+1,
                3.15350626979604161529144E+2,
                -1.01515636749021914166146E+3,
                -3.10777167157231109440444E+3,
                2.25381184209801510330112E+4,
                4.75584627752788110767815E+3,
                -1.34659959864969306392456E+5,
                -1.15132259675553483497211E+5,
            ];

            $num = 0.0;
            $den = 1.0;
            $z = $y - 1;

            for ($i = 0; $i < 8; ++$i) {
                $num = ($num + $p[$i]) * $z;
                $den = $den * $z + $q[$i];
            }

            $result = $num / $den + 1.0;

            if ($lessThanOne) {
                $result /= ($y - 1.0);
            } else {
                for ($i = 0; $i < $n; ++$i) {
                    $result *= $y++;
                }
            }

            return (string) $result;
        }

        if ($operand > 171.624) {
            throw new \RuntimeException('Number too large.');
        }

        return (string) exp(floatval($this->logGamma((string) $operand)));
    }

    /**
     * @param string $operand
     *
     * @return string
     */
    public function logGamma(string $operand): string
    {
        if ($operand <= 0.0) {
            throw new InvalidNumberException('Operand must be a positive number.');
        }

        if ($operand < 12.0) {
            return (string) log(abs($this->gamma((string) $operand)));
        }

        $c = [
            1.0 / 12.0,
            -1.0 / 360.0,
            1.0 / 1260.0,
            -1.0 / 1680.0,
            1.0 / 1188.0,
            -691.0 / 360360.0,
            1.0 / 156.0,
            -3617.0 / 122400.0,
        ];

        $z = 1.0 / ($operand * $operand);
        $sum = $c[7];
        for ($i = 6; $i >= 0; --$i) {
            $sum *= $z;
            $sum += $c[$i];
        }

        $series = $sum / $operand;
        $halfLogTwoPi = 0.91893853320467274178032973640562;
        $logGamma = (floatval($operand) - 0.5) * log(floatval($operand)) - $operand + $halfLogTwoPi + $series;

        return (string) $logGamma;
    }

    /**
     * Figures out the smallest number of decimal places between the two numbers and returns that count.
     * Eg. (1.005, 2.4) => 1, (1.005, 2.5399) => 3.
     *
     * @param string $leftOperand
     * @param string $rightOperand
     *
     * @return int
     */
    private function getSmallestDecimalPlaceCount(string $leftOperand, string $rightOperand): int
    {
        $leftPrecision = DefaultMathAdapter::getNumberPrecision($leftOperand);
        $rightPrecision = DefaultMathAdapter::getNumberPrecision($rightOperand);

        return $leftPrecision < $rightPrecision ? $leftPrecision : $rightPrecision;
    }

    /**
     * Ensures that an operation is meant to be an integer operation, float operation otherwise.
     *
     * @param int $precision
     *
     * @return bool
     */
    private function isIntOperation(int $precision = 0): bool
    {
        return $precision === null || $precision === 0;
    }
}


1		<?php
2
3		namespace Tdn\PhpTypes\Math\Library;
4
5		use Tdn\PhpTypes\Exception\InvalidNumberException;
6		use Tdn\PhpTypes\Math\DefaultMathAdapter;
7		use Tdn\PhpTypes\Type\StringType;
8
9		/**
10		* Class Spl.
11		*/
12		class Spl implements MathLibraryInterface
13		{
14		/**
15		* @var int
16		*/
17		private $roundingStrategy;
18
19		/**
20		* @param int $roundingStrategy a PHP_ROUND_HALF_* integer
21		*/
22	106	public function __construct(int $roundingStrategy)
23		{
24	106	$this->roundingStrategy = $roundingStrategy;
25	106	}
26
27		/**
28		* Add two arbitrary precision numbers.
29		*
30		* @param string $leftOperand
31		* @param string $rightOperand
32		* @param int $precision
33		*
34		* @return string
35		*/
36	1	public function add(string $leftOperand, string $rightOperand, int $precision = 0): string
37		{
38	1	return (string) ($this->isIntOperation($precision) ? (intval($leftOperand) + intval($rightOperand)) :
39	1	round(floatval($leftOperand) + floatval($rightOperand), $precision, $this->roundingStrategy));
40		}
41
42		/**
43		* Subtract two arbitrary precision numbers.
44		*
45		* @param string $leftOperand
46		* @param string $rightOperand
47		* @param int $precision
48		*
49		* @return string
50		*/
51	1	public function subtract(string $leftOperand, string $rightOperand, int $precision = 0): string
52		{
53	1	return (string) ($this->isIntOperation($precision) ? (intval($leftOperand) - intval($rightOperand)) :
54	1	round($leftOperand - $rightOperand, $precision, $this->roundingStrategy));
55		}
56
57		/**
58		* Multiply two arbitrary precision numbers.
59		*
60		* @param string $leftOperand
61		* @param string $rightOperand
62		* @param int $precision
63		*
64		* @return string
65		*/
66	1	public function multiply(string $leftOperand, string $rightOperand, int $precision = 0): string
67		{
68	1	return (string) ($this->isIntOperation($precision) ? (intval($leftOperand) * intval($rightOperand)) :
69	1	round($leftOperand * $rightOperand, ($precision ?? 0), $this->roundingStrategy));
70		}
71
72		/**
73		* Divide two arbitrary precision numbers.
74		*
75		* @param string $leftOperand
76		* @param string $rightOperand
77		* @param int $precision
78		*
79		* @return string
80		*/
81	1	public function divide(string $leftOperand, string $rightOperand, int $precision = 0): string
82		{
83	1	return (string) ($this->isIntOperation($precision) ? (intval($leftOperand) / intval($rightOperand)) :
84	1	round($leftOperand / $rightOperand, $precision, $this->roundingStrategy));
85		}
86
87		/**
88		* Compare two arbitrary precision numbers.
89		*
90		* @param string $leftOperand
91		* @param string $rightOperand
92		* @param int $precision
93		*
94		* @return string
95		*/
96	2	public function compare(string $leftOperand, string $rightOperand, int $precision = 0): string
97		{
98	2	return strval($leftOperand <=> $rightOperand);
99		}
100
101		/**
102		* Get modulus of an arbitrary precision number.
103		*
104		* @param string $operand
105		* @param string $modulus
106		* @param int $precision
107		*
108		* @return string
109		*/
110	3	public function modulus(string $operand, string $modulus, int $precision = 0): string
111		{
112	3	return (string) round(
113	3	fmod(
114	3	floatval($operand),
115	3	floatval($modulus)
116		),
117	3	($precision ?? 0),
118	3	$this->roundingStrategy
119		);
120		}
121
122		/**
123		* Raise an arbitrary precision number to another.
124		*
125		* @param string $leftOperand
126		* @param string $rightOperand
127		* @param int $precision
128		*
129		* @return string
130		*/
131	1	public function power(string $leftOperand, string $rightOperand, int $precision = 0): string
132		{
133	1	return (string) round(
134	1	pow(
135	1	floatval($leftOperand),
136	1	floatval($rightOperand)
137		),
138	1	($precision ?? 0),
139	1	$this->roundingStrategy
140		);
141		}
142
143		/**
144		* Get the square root of an arbitrary precision number.
145		*
146		* @param string $operand
147		* @param int $precision
148		*
149		* @return string
150		*/
151	3	public function squareRoot(string $operand, int $precision = 0): string
152		{
153	3	return (string) round(sqrt(floatval($operand)), ($precision ?? 0), $this->roundingStrategy);
154		}
155
156		/**
157		* Returns absolute value of operand.
158		*
159		* @param string $operand
160		*
161		* @return string
162		*/
163	3	public function absolute(string $operand): string
164		{
165	3	return (string) abs($operand);
166		}
167
168		/**
169		* Negates a number. Opposite of absolute/abs.
170		*
171		* @param string $operand
172		*
173		* @return string
174		*/
175	3	public function negate(string $operand): string
176		{
177	3	return strval($operand * -1);
178		}
179
180		/**
181		* Returns the factorial of operand.
182		*
183		* @param string $operand
184		*
185		* @return string
186		*/
187	1	public function factorial(string $operand): string
188		{
189	1	if (StringType::create($operand)->contains('.')) {
190	1	++$operand;
191
192	1	return $this->gamma((string) $operand);
193		}
194
195		$factorial = function (string $num) use (&$factorial) {
196	1	if ($num < 2) {
197	1	return 1;
198		}
199
200	1	return $factorial(strval($num - 1)) * $num;
201	1	};
202
203	1	return (string) $factorial($operand);
204		}
205
206		/**
207		* Greatest common divisor.
208		*
209		* @param string $leftOperand
210		* @param string $rightOperand
211		*
212		* @return string
213		*/
214		public function gcd(string $leftOperand, string $rightOperand): string
215		{
216	1	$gcd = function (string $a, string $b) use (&$gcd) {
217	1	return $b ? $gcd($b, strval($a % $b)) : $a;
218	1	};
219
220	1	$exponent = $this->getSmallestDecimalPlaceCount($leftOperand, $rightOperand);
221
222		return (string) (
223	1	$gcd(
224	1	strval($leftOperand * (pow(10, $exponent))),
225	1	strval($rightOperand * (pow(10, $exponent)))
226	1	) / pow(10, $exponent)
227		);
228		}
229
230		/**
231		* Calculates to the nth root.
232		*
233		* @param string $operand
234		* @param int $nth
235		*
236		* @return string
237		*/
238	1	public function root(string $operand, int $nth): string
239		{
240		//Implement something later.
241	1	throw new \RuntimeException('Not a valid library for root^n.');
242		}
243
244		/**
245		* Gets the next prime after operand.
246		*
247		* @param string $operand
248		*
249		* @return string
250		*/
251	2	public function nextPrime(string $operand): string
252		{
253	2	$operand = (intval($operand) + 1);
254	2	for ($i = $operand;; ++$i) {
255	2	if ($this->isPrime(strval($i))) {
256	2	break;
257		}
258		}
259
260	2	return (string) $i;
261		}
262
263		/**
264		* @param string $operand
265		* @param int $reps
266		*
267		* @return bool
268		*/
269	3	public function isPrime(string $operand, int $reps = 10): bool
270		{
271	3	$x = floor(sqrt(floatval($operand)));
272	3	for ($i = 2; $i <= $x; ++$i) {
273	3	if (($operand % $i) == 0) {
274	1	break;
275		}
276		}
277
278	3	return ($x == ($i - 1)) ? true : false;
279		}
280
281		/**
282		* Checks if operand is perfect square.
283		*
284		* @param string $operand
285		* @param int $precision
286		*
287		* @return bool
288		*/
289	2	public function isPerfectSquare(string $operand, int $precision = 0): bool
290		{
291	2	$candidate = $this->squareRoot($operand, $precision + 1);
292
293	2	return $candidate == intval($candidate);
294		}
295
296		/**
297		* @return bool
298		*/
299	9	public function isEnabled(): bool
300		{
301	9	return true;
302		}
303
304		/**
305		* @param string $type
306		*
307		* @return bool
308		*/
309	9	public function supportsOperationType(string $type): bool
310		{
311		// Supports both float and int.
312	9	return true;
313		}
314
315		/**
316		* @param string $operand
317		*
318		* @return string
319		*/
320	5	public function gamma(string $operand): string
321		{
322	5	if ($operand <= 0.0) {
323	1	throw new InvalidNumberException('Operand must be a positive number.');
324		}
325
326		// Euler's gamma constant
327	4	$gamma = 0.577215664901532860606512090;
328
329	4	if ($operand < 0.001) {
330	1	return strval(1.0 / ($operand * (1.0 + $gamma * $operand)));
331		}
332
333	4	if ($operand < 12.0) {
334	3	$y = $operand;
335	3	$n = 0;
336	3	$lessThanOne = ($y < 1.0);
337	3	if ($lessThanOne) {
338	2	$y += 1.0;
339		} else {
340		// will use n later
341	3	$n = floor($y) - 1;
342	3	$y -= $n;
343		}
344
345		$p = [
346	3	-1.71618513886549492533811E+0,
347		2.47656508055759199108314E+1,
348		-3.79804256470945635097577E+2,
349		6.29331155312818442661052E+2,
350		8.66966202790413211295064E+2,
351		-3.14512729688483675254357E+4,
352		-3.61444134186911729807069E+4,
353		6.64561438202405440627855E+4,
354		];
355
356		$q = [
357	3	-3.08402300119738975254353E+1,
358		3.15350626979604161529144E+2,
359		-1.01515636749021914166146E+3,
360		-3.10777167157231109440444E+3,
361		2.25381184209801510330112E+4,
362		4.75584627752788110767815E+3,
363		-1.34659959864969306392456E+5,
364		-1.15132259675553483497211E+5,
365		];
366
367	3	$num = 0.0;
368	3	$den = 1.0;
369	3	$z = $y - 1;
370
371	3	for ($i = 0; $i < 8; ++$i) {
372	3	$num = ($num + $p[$i]) * $z;
373	3	$den = $den * $z + $q[$i];
374		}
375
376	3	$result = $num / $den + 1.0;
377
378	3	if ($lessThanOne) {
379	2	$result /= ($y - 1.0);
380		} else {
381	3	for ($i = 0; $i < $n; ++$i) {
382	3	$result *= $y++;
383		}
384		}
385
386	3	return (string) $result;
387		}
388
389	2	if ($operand > 171.624) {
390	1	throw new \RuntimeException('Number too large.');
391		}
392
393	1	return (string) exp(floatval($this->logGamma((string) $operand)));
394		}
395
396		/**
397		* @param string $operand
398		*
399		* @return string
400		*/
401	3	public function logGamma(string $operand): string
402		{
403	3	if ($operand <= 0.0) {
404	1	throw new InvalidNumberException('Operand must be a positive number.');
405		}
406
407	2	if ($operand < 12.0) {
408	1	return (string) log(abs($this->gamma((string) $operand)));
409		}
410
411		$c = [
412	2	1.0 / 12.0,
413		-1.0 / 360.0,
414		1.0 / 1260.0,
415		-1.0 / 1680.0,
416		1.0 / 1188.0,
417		-691.0 / 360360.0,
418		1.0 / 156.0,
419		-3617.0 / 122400.0,
420		];
421
422	2	$z = 1.0 / ($operand * $operand);
423	2	$sum = $c[7];
424	2	for ($i = 6; $i >= 0; --$i) {
425	2	$sum *= $z;
426	2	$sum += $c[$i];
427		}
428
429	2	$series = $sum / $operand;
430	2	$halfLogTwoPi = 0.91893853320467274178032973640562;
431	2	$logGamma = (floatval($operand) - 0.5) * log(floatval($operand)) - $operand + $halfLogTwoPi + $series;
432
433	2	return (string) $logGamma;
434		}
435
436		/**
437		* Figures out the smallest number of decimal places between the two numbers and returns that count.
438		* Eg. (1.005, 2.4) => 1, (1.005, 2.5399) => 3.
439		*
440		* @param string $leftOperand
441		* @param string $rightOperand
442		*
443		* @return int
444		*/
445	1	private function getSmallestDecimalPlaceCount(string $leftOperand, string $rightOperand): int
446		{
447	1	$leftPrecision = DefaultMathAdapter::getNumberPrecision($leftOperand);
448	1	$rightPrecision = DefaultMathAdapter::getNumberPrecision($rightOperand);
449
450	1	return $leftPrecision < $rightPrecision ? $leftPrecision : $rightPrecision;
451		}
452
453		/**
454		* Ensures that an operation is meant to be an integer operation, float operation otherwise.
455		*
456		* @param int $precision
457		*
458		* @return bool
459		*/
460	4	private function isIntOperation(int $precision = 0): bool
461		{
462	4	return $precision === null \|\| $precision === 0;
463		}
464		}
465

TheDevNetwork / PhpTypes

Spl::gamma() C last analyzed 2017-11-18 07:09 UTC

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Spl::gamma() C
last analyzed 2017-11-18 07:09 UTC