tablepress / libraries / vendor / PhpSpreadsheet / Calculation / Statistical / Distributions / Gamma.php

Gamma.php in TablePress – Tables in WordPress made easy 3.4, at libraries/vendor/PhpSpreadsheet/Calculation/Statistical/Distributions/Gamma.php

156 lines 5.0 KB

Raw Download Zip

1	<?php
2
3	namespace TablePress\PhpOffice\PhpSpreadsheet\Calculation\Statistical\Distributions;
4
5	use TablePress\PhpOffice\PhpSpreadsheet\Calculation\ArrayEnabled;
6	use TablePress\PhpOffice\PhpSpreadsheet\Calculation\Exception;
7	use TablePress\PhpOffice\PhpSpreadsheet\Calculation\Information\ExcelError;
8
9	class Gamma extends GammaBase
10	{
11	use ArrayEnabled;
12
13	/**
14	* GAMMA.
15	*
16	* Return the gamma function value.
17	*
18	* @param mixed $value Float value for which we want the probability
19	* Or can be an array of values
20	*
21	* @return array<mixed>\|float\|string The result, or a string containing an error
22	* If an array of numbers is passed as an argument, then the returned result will also be an array
23	* with the same dimensions
24	*/
25	public static function gamma($value)
26	{
27	if (is_array($value)) {
28	return self::evaluateSingleArgumentArray([self::class, __FUNCTION__], $value);
29	}
30
31	try {
32	$value = DistributionValidations::validateFloat($value);
33	} catch (Exception $e) {
34	return $e->getMessage();
35	}
36
37	if ((((int) $value) == ((float) $value)) && $value <= 0.0) {
38	return ExcelError::NAN();
39	}
40
41	return self::gammaValue($value);
42	}
43
44	/**
45	* GAMMADIST.
46	*
47	* Returns the gamma distribution.
48	*
49	* @param mixed $value Float Value at which you want to evaluate the distribution
50	* Or can be an array of values
51	* @param mixed $a Parameter to the distribution as a float
52	* Or can be an array of values
53	* @param mixed $b Parameter to the distribution as a float
54	* Or can be an array of values
55	* @param mixed $cumulative Boolean value indicating if we want the cdf (true) or the pdf (false)
56	* Or can be an array of values
57	*
58	* @return array<mixed>\|float\|string If an array of numbers is passed as an argument, then the returned result will also be an array
59	* with the same dimensions
60	*/
61	public static function distribution($value, $a, $b, $cumulative)
62	{
63	if (is_array($value) \|\| is_array($a) \|\| is_array($b) \|\| is_array($cumulative)) {
64	return self::evaluateArrayArguments([self::class, __FUNCTION__], $value, $a, $b, $cumulative);
65	}
66
67	try {
68	$value = DistributionValidations::validateFloat($value);
69	$a = DistributionValidations::validateFloat($a);
70	$b = DistributionValidations::validateFloat($b);
71	$cumulative = DistributionValidations::validateBool($cumulative);
72	} catch (Exception $e) {
73	return $e->getMessage();
74	}
75
76	if (($value < 0) \|\| ($a <= 0) \|\| ($b <= 0)) {
77	return ExcelError::NAN();
78	}
79
80	return self::calculateDistribution($value, $a, $b, $cumulative);
81	}
82
83	/**
84	* GAMMAINV.
85	*
86	* Returns the inverse of the Gamma distribution.
87	*
88	* For a probability so far into the upper tail that the forward-CDF series
89	* approximation plateaus below it, the root cannot be bracketed; the result
90	* is capped at the alphabeta5 search ceiling rather than diverging.
91	*
92	* @param mixed $probability Float probability at which you want to evaluate the distribution
93	* Or can be an array of values
94	* @param mixed $alpha Parameter to the distribution as a float
95	* Or can be an array of values
96	* @param mixed $beta Parameter to the distribution as a float
97	* Or can be an array of values
98	*
99	* @return array<mixed>\|float\|string If an array of numbers is passed as an argument, then the returned result will also be an array
100	* with the same dimensions
101	*/
102	public static function inverse($probability, $alpha, $beta)
103	{
104	if (is_array($probability) \|\| is_array($alpha) \|\| is_array($beta)) {
105	return self::evaluateArrayArguments([self::class, __FUNCTION__], $probability, $alpha, $beta);
106	}
107
108	try {
109	$probability = DistributionValidations::validateProbability($probability);
110	$alpha = DistributionValidations::validateFloat($alpha);
111	$beta = DistributionValidations::validateFloat($beta);
112	} catch (Exception $e) {
113	return $e->getMessage();
114	}
115
116	if (($alpha <= 0.0) \|\| ($beta <= 0.0)) {
117	return ExcelError::NAN();
118	}
119
120	return self::calculateInverse($probability, $alpha, $beta);
121	}
122
123	/**
124	* GAMMALN.
125	*
126	* Returns the natural logarithm of the gamma function.
127	*
128	* @param mixed $value Float Value at which you want to evaluate the distribution
129	* Or can be an array of values
130	*
131	* @return array<mixed>\|float\|string If an array of numbers is passed as an argument, then the returned result will also be an array
132	* with the same dimensions
133	*/
134	public static function ln($value)
135	{
136	if (is_array($value)) {
137	return self::evaluateSingleArgumentArray([self::class, __FUNCTION__], $value);
138	}
139
140	try {
141	$value = DistributionValidations::validateFloat($value);
142	} catch (Exception $e) {
143	return $e->getMessage();
144	}
145
146	if ($value <= 0) {
147	return ExcelError::NAN();
148	}
149
150	$result = self::logGamma($value);
151
152	// logGamma returns its MAX_VALUE sentinel when the result would overflow.
153	return ($result >= self::MAX_VALUE) ? ExcelError::NAN() : $result;
154	}
155	}
156