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diff --git a/commons-math3-3.6.1/docs/apidocs/org/apache/commons/math3/special/Gamma.html b/commons-math3-3.6.1/docs/apidocs/org/apache/commons/math3/special/Gamma.html new file mode 100644 index 0000000..8c71a13 --- /dev/null +++ b/commons-math3-3.6.1/docs/apidocs/org/apache/commons/math3/special/Gamma.html @@ -0,0 +1,625 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> +<!-- NewPage --> +<html lang="en"> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> +<title>Gamma (Apache Commons Math 3.6.1 API)</title> +<link rel="stylesheet" type="text/css" href="../../../../../stylesheet.css" title="Style"> +</head> +<body> +<script type="text/javascript"><!-- + if (location.href.indexOf('is-external=true') == -1) { + parent.document.title="Gamma (Apache Commons Math 3.6.1 API)"; + } +//--> +</script> +<noscript> +<div>JavaScript is disabled on your browser.</div> +</noscript> +<!-- ========= START OF TOP NAVBAR ======= --> +<div class="topNav"><a name="navbar_top"> +<!-- --> +</a><a href="#skip-navbar_top" title="Skip navigation links"></a><a name="navbar_top_firstrow"> +<!-- --> +</a> +<ul class="navList" title="Navigation"> +<li><a href="../../../../../overview-summary.html">Overview</a></li> +<li><a href="package-summary.html">Package</a></li> +<li class="navBarCell1Rev">Class</li> +<li><a href="class-use/Gamma.html">Use</a></li> +<li><a href="package-tree.html">Tree</a></li> +<li><a href="../../../../../deprecated-list.html">Deprecated</a></li> +<li><a href="../../../../../index-all.html">Index</a></li> +<li><a href="../../../../../help-doc.html">Help</a></li> +</ul> +<div class="aboutLanguage"><em><script type="text/javascript" src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script></em></div> +</div> +<div class="subNav"> +<ul class="navList"> +<li><a href="../../../../../org/apache/commons/math3/special/Erf.html" title="class in org.apache.commons.math3.special"><span class="strong">Prev Class</span></a></li> +<li>Next Class</li> +</ul> +<ul class="navList"> +<li><a href="../../../../../index.html?org/apache/commons/math3/special/Gamma.html" target="_top">Frames</a></li> +<li><a href="Gamma.html" target="_top">No Frames</a></li> +</ul> +<ul class="navList" id="allclasses_navbar_top"> +<li><a href="../../../../../allclasses-noframe.html">All Classes</a></li> +</ul> +<div> +<script type="text/javascript"><!-- + allClassesLink = document.getElementById("allclasses_navbar_top"); 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Since no such notice appears in the code these + functions can safely be ported to Commons-Math. + </p></div> +</li> +</ul> +</div> +<div class="summary"> +<ul class="blockList"> +<li class="blockList"> +<!-- =========== FIELD SUMMARY =========== --> +<ul class="blockList"> +<li class="blockList"><a name="field_summary"> +<!-- --> +</a> +<h3>Field Summary</h3> +<table class="overviewSummary" border="0" cellpadding="3" cellspacing="0" summary="Field Summary table, listing fields, and an explanation"> +<caption><span>Fields</span><span class="tabEnd"> </span></caption> +<tr> +<th class="colFirst" scope="col">Modifier and Type</th> +<th class="colLast" scope="col">Field and Description</th> +</tr> +<tr class="altColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#GAMMA">GAMMA</a></strong></code> +<div class="block"><a href="http://en.wikipedia.org/wiki/Euler-Mascheroni_constant">Euler-Mascheroni constant</a></div> +</td> +</tr> +<tr class="rowColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#LANCZOS_G">LANCZOS_G</a></strong></code> +<div class="block">The value of the <code>g</code> constant in the Lanczos approximation, see + <a href="../../../../../org/apache/commons/math3/special/Gamma.html#lanczos(double)"><code>lanczos(double)</code></a>.</div> +</td> +</tr> +</table> +</li> +</ul> +<!-- ========== METHOD SUMMARY =========== --> +<ul class="blockList"> +<li class="blockList"><a name="method_summary"> +<!-- --> +</a> +<h3>Method Summary</h3> +<table class="overviewSummary" border="0" cellpadding="3" cellspacing="0" summary="Method Summary table, listing methods, and an explanation"> +<caption><span>Methods</span><span class="tabEnd"> </span></caption> +<tr> +<th class="colFirst" scope="col">Modifier and Type</th> +<th class="colLast" scope="col">Method and Description</th> +</tr> +<tr class="altColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#digamma(double)">digamma</a></strong>(double x)</code> +<div class="block">Computes the digamma function of x.</div> +</td> +</tr> +<tr class="rowColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#gamma(double)">gamma</a></strong>(double x)</code> +<div class="block">Returns the value of Γ(x).</div> +</td> +</tr> +<tr class="altColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#invGamma1pm1(double)">invGamma1pm1</a></strong>(double x)</code> +<div class="block">Returns the value of 1 / Γ(1 + x) - 1 for -0.5 ≤ x ≤ + 1.5.</div> +</td> +</tr> +<tr class="rowColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#lanczos(double)">lanczos</a></strong>(double x)</code> +<div class="block"> + Returns the Lanczos approximation used to compute the gamma function.</div> +</td> +</tr> +<tr class="altColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#logGamma(double)">logGamma</a></strong>(double x)</code> +<div class="block"> + Returns the value of log Γ(x) for x > 0.</div> +</td> +</tr> +<tr class="rowColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#logGamma1p(double)">logGamma1p</a></strong>(double x)</code> +<div class="block">Returns the value of log Γ(1 + x) for -0.5 ≤ x ≤ 1.5.</div> +</td> +</tr> +<tr class="altColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#regularizedGammaP(double,%20double)">regularizedGammaP</a></strong>(double a, + double x)</code> +<div class="block">Returns the regularized gamma function P(a, x).</div> +</td> +</tr> +<tr class="rowColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#regularizedGammaP(double,%20double,%20double,%20int)">regularizedGammaP</a></strong>(double a, + double x, + double epsilon, + int maxIterations)</code> +<div class="block">Returns the regularized gamma function P(a, x).</div> +</td> +</tr> +<tr class="altColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#regularizedGammaQ(double,%20double)">regularizedGammaQ</a></strong>(double a, + double x)</code> +<div class="block">Returns the regularized gamma function Q(a, x) = 1 - P(a, x).</div> +</td> +</tr> +<tr class="rowColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#regularizedGammaQ(double,%20double,%20double,%20int)">regularizedGammaQ</a></strong>(double a, + double x, + double epsilon, + int maxIterations)</code> +<div class="block">Returns the regularized gamma function Q(a, x) = 1 - P(a, x).</div> +</td> +</tr> +<tr class="altColor"> +<td class="colFirst"><code>static double</code></td> +<td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/special/Gamma.html#trigamma(double)">trigamma</a></strong>(double x)</code> +<div class="block">Computes the trigamma function of x.</div> +</td> +</tr> +</table> +<ul class="blockList"> +<li class="blockList"><a name="methods_inherited_from_class_java.lang.Object"> +<!-- --> +</a> +<h3>Methods inherited from class java.lang.<a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</a></h3> +<code><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#clone()" title="class or interface in java.lang">clone</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#equals(java.lang.Object)" title="class or interface in java.lang">equals</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#finalize()" title="class or interface in java.lang">finalize</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#getClass()" title="class or interface in java.lang">getClass</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#hashCode()" title="class or interface in java.lang">hashCode</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#notify()" title="class or interface in java.lang">notify</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#notifyAll()" title="class or interface in java.lang">notifyAll</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#toString()" title="class or interface in java.lang">toString</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#wait()" title="class or interface in java.lang">wait</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#wait(long)" title="class or interface in java.lang">wait</a>, <a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Object.html?is-external=true#wait(long,%20int)" title="class or interface in java.lang">wait</a></code></li> +</ul> +</li> +</ul> +</li> +</ul> +</div> +<div class="details"> +<ul class="blockList"> +<li class="blockList"> +<!-- ============ FIELD DETAIL =========== --> +<ul class="blockList"> +<li class="blockList"><a name="field_detail"> +<!-- --> +</a> +<h3>Field Detail</h3> +<a name="GAMMA"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>GAMMA</h4> +<pre>public static final double GAMMA</pre> +<div class="block"><a href="http://en.wikipedia.org/wiki/Euler-Mascheroni_constant">Euler-Mascheroni constant</a></div> +<dl><dt><span class="strong">Since:</span></dt> + <dd>2.0</dd> +<dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../constant-values.html#org.apache.commons.math3.special.Gamma.GAMMA">Constant Field Values</a></dd></dl> +</li> +</ul> +<a name="LANCZOS_G"> +<!-- --> +</a> +<ul class="blockListLast"> +<li class="blockList"> +<h4>LANCZOS_G</h4> +<pre>public static final double LANCZOS_G</pre> +<div class="block">The value of the <code>g</code> constant in the Lanczos approximation, see + <a href="../../../../../org/apache/commons/math3/special/Gamma.html#lanczos(double)"><code>lanczos(double)</code></a>.</div> +<dl><dt><span class="strong">Since:</span></dt> + <dd>3.1</dd> +<dt><span class="strong">See Also:</span></dt><dd><a href="../../../../../constant-values.html#org.apache.commons.math3.special.Gamma.LANCZOS_G">Constant Field Values</a></dd></dl> +</li> +</ul> +</li> +</ul> +<!-- ============ METHOD DETAIL ========== --> +<ul class="blockList"> +<li class="blockList"><a name="method_detail"> +<!-- --> +</a> +<h3>Method Detail</h3> +<a name="logGamma(double)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>logGamma</h4> +<pre>public static double logGamma(double x)</pre> +<div class="block"><p> + Returns the value of log Γ(x) for x > 0. + </p> + <p> + For x ≤ 8, the implementation is based on the double precision + implementation in the <em>NSWC Library of Mathematics Subroutines</em>, + <code>DGAMLN</code>. For x > 8, the implementation is based on + </p> + <ul> + <li><a href="http://mathworld.wolfram.com/GammaFunction.html">Gamma + Function</a>, equation (28).</li> + <li><a href="http://mathworld.wolfram.com/LanczosApproximation.html"> + Lanczos Approximation</a>, equations (1) through (5).</li> + <li><a href="http://my.fit.edu/~gabdo/gamma.txt">Paul Godfrey, A note on + the computation of the convergent Lanczos complex Gamma + approximation</a></li> + </ul></div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>x</code> - Argument.</dd> +<dt><span class="strong">Returns:</span></dt><dd>the value of <code>log(Gamma(x))</code>, <code>Double.NaN</code> if + <code>x <= 0.0</code>.</dd></dl> +</li> +</ul> +<a name="regularizedGammaP(double, double)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>regularizedGammaP</h4> +<pre>public static double regularizedGammaP(double a, + double x)</pre> +<div class="block">Returns the regularized gamma function P(a, x).</div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>a</code> - Parameter.</dd><dd><code>x</code> - Value.</dd> +<dt><span class="strong">Returns:</span></dt><dd>the regularized gamma function P(a, x).</dd> +<dt><span class="strong">Throws:</span></dt> +<dd><code><a href="../../../../../org/apache/commons/math3/exception/MaxCountExceededException.html" title="class in org.apache.commons.math3.exception">MaxCountExceededException</a></code> - if the algorithm fails to converge.</dd></dl> +</li> +</ul> +<a name="regularizedGammaP(double, double, double, int)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>regularizedGammaP</h4> +<pre>public static double regularizedGammaP(double a, + double x, + double epsilon, + int maxIterations)</pre> +<div class="block">Returns the regularized gamma function P(a, x). + + The implementation of this method is based on: + <ul> + <li> + <a href="http://mathworld.wolfram.com/RegularizedGammaFunction.html"> + Regularized Gamma Function</a>, equation (1) + </li> + <li> + <a href="http://mathworld.wolfram.com/IncompleteGammaFunction.html"> + Incomplete Gamma Function</a>, equation (4). + </li> + <li> + <a href="http://mathworld.wolfram.com/ConfluentHypergeometricFunctionoftheFirstKind.html"> + Confluent Hypergeometric Function of the First Kind</a>, equation (1). + </li> + </ul></div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>a</code> - the a parameter.</dd><dd><code>x</code> - the value.</dd><dd><code>epsilon</code> - When the absolute value of the nth item in the + series is less than epsilon the approximation ceases to calculate + further elements in the series.</dd><dd><code>maxIterations</code> - Maximum number of "iterations" to complete.</dd> +<dt><span class="strong">Returns:</span></dt><dd>the regularized gamma function P(a, x)</dd> +<dt><span class="strong">Throws:</span></dt> +<dd><code><a href="../../../../../org/apache/commons/math3/exception/MaxCountExceededException.html" title="class in org.apache.commons.math3.exception">MaxCountExceededException</a></code> - if the algorithm fails to converge.</dd></dl> +</li> +</ul> +<a name="regularizedGammaQ(double, double)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>regularizedGammaQ</h4> +<pre>public static double regularizedGammaQ(double a, + double x)</pre> +<div class="block">Returns the regularized gamma function Q(a, x) = 1 - P(a, x).</div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>a</code> - the a parameter.</dd><dd><code>x</code> - the value.</dd> +<dt><span class="strong">Returns:</span></dt><dd>the regularized gamma function Q(a, x)</dd> +<dt><span class="strong">Throws:</span></dt> +<dd><code><a href="../../../../../org/apache/commons/math3/exception/MaxCountExceededException.html" title="class in org.apache.commons.math3.exception">MaxCountExceededException</a></code> - if the algorithm fails to converge.</dd></dl> +</li> +</ul> +<a name="regularizedGammaQ(double, double, double, int)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>regularizedGammaQ</h4> +<pre>public static double regularizedGammaQ(double a, + double x, + double epsilon, + int maxIterations)</pre> +<div class="block">Returns the regularized gamma function Q(a, x) = 1 - P(a, x). + + The implementation of this method is based on: + <ul> + <li> + <a href="http://mathworld.wolfram.com/RegularizedGammaFunction.html"> + Regularized Gamma Function</a>, equation (1). + </li> + <li> + <a href="http://functions.wolfram.com/GammaBetaErf/GammaRegularized/10/0003/"> + Regularized incomplete gamma function: Continued fraction representations + (formula 06.08.10.0003)</a> + </li> + </ul></div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>a</code> - the a parameter.</dd><dd><code>x</code> - the value.</dd><dd><code>epsilon</code> - When the absolute value of the nth item in the + series is less than epsilon the approximation ceases to calculate + further elements in the series.</dd><dd><code>maxIterations</code> - Maximum number of "iterations" to complete.</dd> +<dt><span class="strong">Returns:</span></dt><dd>the regularized gamma function P(a, x)</dd> +<dt><span class="strong">Throws:</span></dt> +<dd><code><a href="../../../../../org/apache/commons/math3/exception/MaxCountExceededException.html" title="class in org.apache.commons.math3.exception">MaxCountExceededException</a></code> - if the algorithm fails to converge.</dd></dl> +</li> +</ul> +<a name="digamma(double)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>digamma</h4> +<pre>public static double digamma(double x)</pre> +<div class="block"><p>Computes the digamma function of x.</p> + + <p>This is an independently written implementation of the algorithm described in + Jose Bernardo, Algorithm AS 103: Psi (Digamma) Function, Applied Statistics, 1976.</p> + + <p>Some of the constants have been changed to increase accuracy at the moderate expense + of run-time. The result should be accurate to within 10^-8 absolute tolerance for + x >= 10^-5 and within 10^-8 relative tolerance for x > 0.</p> + + <p>Performance for large negative values of x will be quite expensive (proportional to + |x|). Accuracy for negative values of x should be about 10^-8 absolute for results + less than 10^5 and 10^-8 relative for results larger than that.</p></div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>x</code> - Argument.</dd> +<dt><span class="strong">Returns:</span></dt><dd>digamma(x) to within 10-8 relative or absolute error whichever is smaller.</dd><dt><span class="strong">Since:</span></dt> + <dd>2.0</dd> +<dt><span class="strong">See Also:</span></dt><dd><a href="http://en.wikipedia.org/wiki/Digamma_function">Digamma</a>, +<a href="http://www.uv.es/~bernardo/1976AppStatist.pdf">Bernardo's original article </a></dd></dl> +</li> +</ul> +<a name="trigamma(double)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>trigamma</h4> +<pre>public static double trigamma(double x)</pre> +<div class="block">Computes the trigamma function of x. + This function is derived by taking the derivative of the implementation + of digamma.</div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>x</code> - Argument.</dd> +<dt><span class="strong">Returns:</span></dt><dd>trigamma(x) to within 10-8 relative or absolute error whichever is smaller</dd><dt><span class="strong">Since:</span></dt> + <dd>2.0</dd> +<dt><span class="strong">See Also:</span></dt><dd><a href="http://en.wikipedia.org/wiki/Trigamma_function">Trigamma</a>, +<a href="../../../../../org/apache/commons/math3/special/Gamma.html#digamma(double)"><code>digamma(double)</code></a></dd></dl> +</li> +</ul> +<a name="lanczos(double)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>lanczos</h4> +<pre>public static double lanczos(double x)</pre> +<div class="block"><p> + Returns the Lanczos approximation used to compute the gamma function. + The Lanczos approximation is related to the Gamma function by the + following equation + <center> + <code>gamma(x) = sqrt(2 * pi) / x * (x + g + 0.5) ^ (x + 0.5) + * exp(-x - g - 0.5) * lanczos(x)</code>, + </center> + where <code>g</code> is the Lanczos constant. + </p></div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>x</code> - Argument.</dd> +<dt><span class="strong">Returns:</span></dt><dd>The Lanczos approximation.</dd><dt><span class="strong">Since:</span></dt> + <dd>3.1</dd> +<dt><span class="strong">See Also:</span></dt><dd><a href="http://mathworld.wolfram.com/LanczosApproximation.html">Lanczos Approximation</a> + equations (1) through (5), and Paul Godfrey's + <a href="http://my.fit.edu/~gabdo/gamma.txt">Note on the computation + of the convergent Lanczos complex Gamma approximation</a></dd></dl> +</li> +</ul> +<a name="invGamma1pm1(double)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>invGamma1pm1</h4> +<pre>public static double invGamma1pm1(double x)</pre> +<div class="block">Returns the value of 1 / Γ(1 + x) - 1 for -0.5 ≤ x ≤ + 1.5. This implementation is based on the double precision + implementation in the <em>NSWC Library of Mathematics Subroutines</em>, + <code>DGAM1</code>.</div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>x</code> - Argument.</dd> +<dt><span class="strong">Returns:</span></dt><dd>The value of <code>1.0 / Gamma(1.0 + x) - 1.0</code>.</dd> +<dt><span class="strong">Throws:</span></dt> +<dd><code><a href="../../../../../org/apache/commons/math3/exception/NumberIsTooSmallException.html" title="class in org.apache.commons.math3.exception">NumberIsTooSmallException</a></code> - if <code>x < -0.5</code></dd> +<dd><code><a href="../../../../../org/apache/commons/math3/exception/NumberIsTooLargeException.html" title="class in org.apache.commons.math3.exception">NumberIsTooLargeException</a></code> - if <code>x > 1.5</code></dd><dt><span class="strong">Since:</span></dt> + <dd>3.1</dd></dl> +</li> +</ul> +<a name="logGamma1p(double)"> +<!-- --> +</a> +<ul class="blockList"> +<li class="blockList"> +<h4>logGamma1p</h4> +<pre>public static double logGamma1p(double x) + throws <a href="../../../../../org/apache/commons/math3/exception/NumberIsTooSmallException.html" title="class in org.apache.commons.math3.exception">NumberIsTooSmallException</a>, + <a href="../../../../../org/apache/commons/math3/exception/NumberIsTooLargeException.html" title="class in org.apache.commons.math3.exception">NumberIsTooLargeException</a></pre> +<div class="block">Returns the value of log Γ(1 + x) for -0.5 ≤ x ≤ 1.5. + This implementation is based on the double precision implementation in + the <em>NSWC Library of Mathematics Subroutines</em>, <code>DGMLN1</code>.</div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>x</code> - Argument.</dd> +<dt><span class="strong">Returns:</span></dt><dd>The value of <code>log(Gamma(1 + x))</code>.</dd> +<dt><span class="strong">Throws:</span></dt> +<dd><code><a href="../../../../../org/apache/commons/math3/exception/NumberIsTooSmallException.html" title="class in org.apache.commons.math3.exception">NumberIsTooSmallException</a></code> - if <code>x < -0.5</code>.</dd> +<dd><code><a href="../../../../../org/apache/commons/math3/exception/NumberIsTooLargeException.html" title="class in org.apache.commons.math3.exception">NumberIsTooLargeException</a></code> - if <code>x > 1.5</code>.</dd><dt><span class="strong">Since:</span></dt> + <dd>3.1</dd></dl> +</li> +</ul> +<a name="gamma(double)"> +<!-- --> +</a> +<ul class="blockListLast"> +<li class="blockList"> +<h4>gamma</h4> +<pre>public static double gamma(double x)</pre> +<div class="block">Returns the value of Γ(x). Based on the <em>NSWC Library of + Mathematics Subroutines</em> double precision implementation, + <code>DGAMMA</code>.</div> +<dl><dt><span class="strong">Parameters:</span></dt><dd><code>x</code> - Argument.</dd> +<dt><span class="strong">Returns:</span></dt><dd>the value of <code>Gamma(x)</code>.</dd><dt><span class="strong">Since:</span></dt> + <dd>3.1</dd></dl> +</li> +</ul> +</li> +</ul> +</li> +</ul> +</div> +</div> +<!-- ========= END OF CLASS DATA ========= --> +<!-- ======= START OF BOTTOM NAVBAR ====== --> +<div class="bottomNav"><a name="navbar_bottom"> +<!-- --> +</a><a href="#skip-navbar_bottom" title="Skip navigation links"></a><a name="navbar_bottom_firstrow"> +<!-- --> +</a> +<ul class="navList" title="Navigation"> +<li><a href="../../../../../overview-summary.html">Overview</a></li> +<li><a href="package-summary.html">Package</a></li> +<li class="navBarCell1Rev">Class</li> +<li><a href="class-use/Gamma.html">Use</a></li> +<li><a href="package-tree.html">Tree</a></li> +<li><a href="../../../../../deprecated-list.html">Deprecated</a></li> +<li><a href="../../../../../index-all.html">Index</a></li> +<li><a href="../../../../../help-doc.html">Help</a></li> +</ul> +<div class="aboutLanguage"><em><script type="text/javascript" src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script></em></div> +</div> +<div class="subNav"> +<ul class="navList"> +<li><a href="../../../../../org/apache/commons/math3/special/Erf.html" title="class in org.apache.commons.math3.special"><span class="strong">Prev Class</span></a></li> +<li>Next Class</li> +</ul> +<ul class="navList"> +<li><a href="../../../../../index.html?org/apache/commons/math3/special/Gamma.html" target="_top">Frames</a></li> +<li><a href="Gamma.html" target="_top">No Frames</a></li> +</ul> +<ul class="navList" id="allclasses_navbar_bottom"> +<li><a href="../../../../../allclasses-noframe.html">All Classes</a></li> +</ul> +<div> +<script type="text/javascript"><!-- + allClassesLink = document.getElementById("allclasses_navbar_bottom"); + if(window==top) { + allClassesLink.style.display = "block"; + } + else { + allClassesLink.style.display = "none"; + } + //--> +</script> +</div> +<div> +<ul class="subNavList"> +<li>Summary: </li> +<li>Nested | </li> +<li><a href="#field_summary">Field</a> | </li> +<li>Constr | </li> +<li><a href="#method_summary">Method</a></li> +</ul> +<ul class="subNavList"> +<li>Detail: </li> +<li><a href="#field_detail">Field</a> | </li> +<li>Constr | </li> +<li><a href="#method_detail">Method</a></li> +</ul> +</div> +<a name="skip-navbar_bottom"> +<!-- --> +</a></div> +<!-- ======== END OF BOTTOM NAVBAR ======= --> +<p class="legalCopy"><small>Copyright © 2003–2016 <a href="http://www.apache.org/">The Apache Software Foundation</a>. 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