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| <h2 title="Class CombinatoricsUtils" class="title">Class CombinatoricsUtils</h2> |
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| <ul class="inheritance"> |
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| <ul class="inheritance"> |
| <li>org.apache.commons.math3.util.CombinatoricsUtils</li> |
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| <pre>public final class <span class="strong">CombinatoricsUtils</span> |
| extends <a href="http://docs.oracle.com/javase/6/docs/api/java/lang/Object.html?is-external=true" title="class or interface in java.lang">Object</a></pre> |
| <div class="block">Combinatorial utilities.</div> |
| <dl><dt><span class="strong">Since:</span></dt> |
| <dd>3.3</dd> |
| <dt><span class="strong">Version:</span></dt> |
| <dd>$Id$</dd></dl> |
| </li> |
| </ul> |
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| <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 long</code></td> |
| <td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/util/CombinatoricsUtils.html#binomialCoefficient(int, int)">binomialCoefficient</a></strong>(int n, |
| int k)</code> |
| <div class="block">Returns an exact representation of the <a |
| href="http://mathworld.wolfram.com/BinomialCoefficient.html"> Binomial |
| Coefficient</a>, "<code>n choose k</code>", the number of |
| <code>k</code>-element subsets that can be selected from an |
| <code>n</code>-element set.</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/util/CombinatoricsUtils.html#binomialCoefficientDouble(int, int)">binomialCoefficientDouble</a></strong>(int n, |
| int k)</code> |
| <div class="block">Returns a <code>double</code> representation of the <a |
| href="http://mathworld.wolfram.com/BinomialCoefficient.html"> Binomial |
| Coefficient</a>, "<code>n choose k</code>", the number of |
| <code>k</code>-element subsets that can be selected from an |
| <code>n</code>-element set.</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/util/CombinatoricsUtils.html#binomialCoefficientLog(int, int)">binomialCoefficientLog</a></strong>(int n, |
| int k)</code> |
| <div class="block">Returns the natural <code>log</code> of the <a |
| href="http://mathworld.wolfram.com/BinomialCoefficient.html"> Binomial |
| Coefficient</a>, "<code>n choose k</code>", the number of |
| <code>k</code>-element subsets that can be selected from an |
| <code>n</code>-element set.</div> |
| </td> |
| </tr> |
| <tr class="rowColor"> |
| <td class="colFirst"><code>static void</code></td> |
| <td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/util/CombinatoricsUtils.html#checkBinomial(int, int)">checkBinomial</a></strong>(int n, |
| int k)</code> |
| <div class="block">Check binomial preconditions.</div> |
| </td> |
| </tr> |
| <tr class="altColor"> |
| <td class="colFirst"><code>static <a href="http://docs.oracle.com/javase/6/docs/api/java/util/Iterator.html?is-external=true" title="class or interface in java.util">Iterator</a><int[]></code></td> |
| <td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/util/CombinatoricsUtils.html#combinationsIterator(int, int)">combinationsIterator</a></strong>(int n, |
| int k)</code> |
| <div class="block">Returns an iterator whose range is the k-element subsets of {0, ..., n - 1} |
| represented as <code>int[]</code> arrays.</div> |
| </td> |
| </tr> |
| <tr class="rowColor"> |
| <td class="colFirst"><code>static long</code></td> |
| <td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/util/CombinatoricsUtils.html#factorial(int)">factorial</a></strong>(int n)</code> |
| <div class="block">Returns n!.</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/util/CombinatoricsUtils.html#factorialDouble(int)">factorialDouble</a></strong>(int n)</code> |
| <div class="block">Compute n!, the<a href="http://mathworld.wolfram.com/Factorial.html"> |
| factorial</a> of <code>n</code> (the product of the numbers 1 to n), as a |
| <code>double</code>.</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/util/CombinatoricsUtils.html#factorialLog(int)">factorialLog</a></strong>(int n)</code> |
| <div class="block">Compute the natural logarithm of the factorial of <code>n</code>.</div> |
| </td> |
| </tr> |
| <tr class="altColor"> |
| <td class="colFirst"><code>static long</code></td> |
| <td class="colLast"><code><strong><a href="../../../../../org/apache/commons/math3/util/CombinatoricsUtils.html#stirlingS2(int, int)">stirlingS2</a></strong>(int n, |
| int k)</code> |
| <div class="block">Returns the <a |
| href="http://mathworld.wolfram.com/StirlingNumberoftheSecondKind.html"> |
| Stirling number of the second kind</a>, "<code>S(n,k)</code>", the number of |
| ways of partitioning an <code>n</code>-element set into <code>k</code> non-empty |
| subsets.</div> |
| </td> |
| </tr> |
| </table> |
| <ul class="blockList"> |
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| <h3>Methods inherited from class java.lang.<a href="http://docs.oracle.com/javase/6/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/6/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/6/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/6/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/6/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/6/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/6/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/6/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/6/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/6/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/6/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/6/docs/api/java/lang/Object.html?is-external=true#wait(long, int)" title="class or interface in java.lang">wait</a></code></li> |
| </ul> |
| </li> |
| </ul> |
| </li> |
| </ul> |
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| <h3>Method Detail</h3> |
| <a name="binomialCoefficient(int, int)"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>binomialCoefficient</h4> |
| <pre>public static long binomialCoefficient(int n, |
| int k) |
| throws <a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/NumberIsTooLargeException.html" title="class in org.apache.commons.math3.exception">NumberIsTooLargeException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></pre> |
| <div class="block">Returns an exact representation of the <a |
| href="http://mathworld.wolfram.com/BinomialCoefficient.html"> Binomial |
| Coefficient</a>, "<code>n choose k</code>", the number of |
| <code>k</code>-element subsets that can be selected from an |
| <code>n</code>-element set. |
| <p> |
| <Strong>Preconditions</strong>: |
| <ul> |
| <li> <code>0 <= k <= n </code> (otherwise |
| <code>MathIllegalArgumentException</code> is thrown)</li> |
| <li> The result is small enough to fit into a <code>long</code>. The |
| largest value of <code>n</code> for which all coefficients are |
| <code>< Long.MAX_VALUE</code> is 66. If the computed value exceeds |
| <code>Long.MAX_VALUE</code> an <code>ArithMeticException</code> is |
| thrown.</li> |
| </ul></p></div> |
| <dl><dt><span class="strong">Parameters:</span></dt><dd><code>n</code> - the size of the set</dd><dd><code>k</code> - the size of the subsets to be counted</dd> |
| <dt><span class="strong">Returns:</span></dt><dd><code>n choose k</code></dd> |
| <dt><span class="strong">Throws:</span></dt> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></code> - if <code>n < 0</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>k > n</code>.</dd> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></code> - if the result is too large to be |
| represented by a long integer.</dd></dl> |
| </li> |
| </ul> |
| <a name="binomialCoefficientDouble(int, int)"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
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| <h4>binomialCoefficientDouble</h4> |
| <pre>public static double binomialCoefficientDouble(int n, |
| int k) |
| throws <a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/NumberIsTooLargeException.html" title="class in org.apache.commons.math3.exception">NumberIsTooLargeException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></pre> |
| <div class="block">Returns a <code>double</code> representation of the <a |
| href="http://mathworld.wolfram.com/BinomialCoefficient.html"> Binomial |
| Coefficient</a>, "<code>n choose k</code>", the number of |
| <code>k</code>-element subsets that can be selected from an |
| <code>n</code>-element set. |
| <p> |
| <Strong>Preconditions</strong>: |
| <ul> |
| <li> <code>0 <= k <= n </code> (otherwise |
| <code>IllegalArgumentException</code> is thrown)</li> |
| <li> The result is small enough to fit into a <code>double</code>. The |
| largest value of <code>n</code> for which all coefficients are < |
| Double.MAX_VALUE is 1029. If the computed value exceeds Double.MAX_VALUE, |
| Double.POSITIVE_INFINITY is returned</li> |
| </ul></p></div> |
| <dl><dt><span class="strong">Parameters:</span></dt><dd><code>n</code> - the size of the set</dd><dd><code>k</code> - the size of the subsets to be counted</dd> |
| <dt><span class="strong">Returns:</span></dt><dd><code>n choose k</code></dd> |
| <dt><span class="strong">Throws:</span></dt> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></code> - if <code>n < 0</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>k > n</code>.</dd> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></code> - if the result is too large to be |
| represented by a long integer.</dd></dl> |
| </li> |
| </ul> |
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| </a> |
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| <li class="blockList"> |
| <h4>binomialCoefficientLog</h4> |
| <pre>public static double binomialCoefficientLog(int n, |
| int k) |
| throws <a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/NumberIsTooLargeException.html" title="class in org.apache.commons.math3.exception">NumberIsTooLargeException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></pre> |
| <div class="block">Returns the natural <code>log</code> of the <a |
| href="http://mathworld.wolfram.com/BinomialCoefficient.html"> Binomial |
| Coefficient</a>, "<code>n choose k</code>", the number of |
| <code>k</code>-element subsets that can be selected from an |
| <code>n</code>-element set. |
| <p> |
| <Strong>Preconditions</strong>: |
| <ul> |
| <li> <code>0 <= k <= n </code> (otherwise |
| <code>IllegalArgumentException</code> is thrown)</li> |
| </ul></p></div> |
| <dl><dt><span class="strong">Parameters:</span></dt><dd><code>n</code> - the size of the set</dd><dd><code>k</code> - the size of the subsets to be counted</dd> |
| <dt><span class="strong">Returns:</span></dt><dd><code>n choose k</code></dd> |
| <dt><span class="strong">Throws:</span></dt> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></code> - if <code>n < 0</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>k > n</code>.</dd> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></code> - if the result is too large to be |
| represented by a long integer.</dd></dl> |
| </li> |
| </ul> |
| <a name="factorial(int)"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>factorial</h4> |
| <pre>public static long factorial(int n) |
| throws <a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></pre> |
| <div class="block">Returns n!. Shorthand for <code>n</code> <a |
| href="http://mathworld.wolfram.com/Factorial.html"> Factorial</a>, the |
| product of the numbers <code>1,...,n</code>. |
| <p> |
| <Strong>Preconditions</strong>: |
| <ul> |
| <li> <code>n >= 0</code> (otherwise |
| <code>IllegalArgumentException</code> is thrown)</li> |
| <li> The result is small enough to fit into a <code>long</code>. The |
| largest value of <code>n</code> for which <code>n!</code> < |
| Long.MAX_VALUE} is 20. If the computed value exceeds <code>Long.MAX_VALUE</code> |
| an <code>ArithMeticException </code> is thrown.</li> |
| </ul> |
| </p></div> |
| <dl><dt><span class="strong">Parameters:</span></dt><dd><code>n</code> - argument</dd> |
| <dt><span class="strong">Returns:</span></dt><dd><code>n!</code></dd> |
| <dt><span class="strong">Throws:</span></dt> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></code> - if the result is too large to be represented |
| by a <code>long</code>.</dd> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></code> - if <code>n < 0</code>.</dd> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></code> - if <code>n > 20</code>: The factorial value is too |
| large to fit in a <code>long</code>.</dd></dl> |
| </li> |
| </ul> |
| <a name="factorialDouble(int)"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>factorialDouble</h4> |
| <pre>public static double factorialDouble(int n) |
| throws <a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></pre> |
| <div class="block">Compute n!, the<a href="http://mathworld.wolfram.com/Factorial.html"> |
| factorial</a> of <code>n</code> (the product of the numbers 1 to n), as a |
| <code>double</code>. |
| The result should be small enough to fit into a <code>double</code>: The |
| largest <code>n</code> for which <code>n! < Double.MAX_VALUE</code> is 170. |
| If the computed value exceeds <code>Double.MAX_VALUE</code>, |
| <code>Double.POSITIVE_INFINITY</code> is returned.</div> |
| <dl><dt><span class="strong">Parameters:</span></dt><dd><code>n</code> - Argument.</dd> |
| <dt><span class="strong">Returns:</span></dt><dd><code>n!</code></dd> |
| <dt><span class="strong">Throws:</span></dt> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></code> - if <code>n < 0</code>.</dd></dl> |
| </li> |
| </ul> |
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| </a> |
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| <h4>factorialLog</h4> |
| <pre>public static double factorialLog(int n) |
| throws <a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></pre> |
| <div class="block">Compute the natural logarithm of the factorial of <code>n</code>.</div> |
| <dl><dt><span class="strong">Parameters:</span></dt><dd><code>n</code> - Argument.</dd> |
| <dt><span class="strong">Returns:</span></dt><dd><code>n!</code></dd> |
| <dt><span class="strong">Throws:</span></dt> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></code> - if <code>n < 0</code>.</dd></dl> |
| </li> |
| </ul> |
| <a name="stirlingS2(int, int)"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>stirlingS2</h4> |
| <pre>public static long stirlingS2(int n, |
| int k) |
| throws <a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/NumberIsTooLargeException.html" title="class in org.apache.commons.math3.exception">NumberIsTooLargeException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></pre> |
| <div class="block">Returns the <a |
| href="http://mathworld.wolfram.com/StirlingNumberoftheSecondKind.html"> |
| Stirling number of the second kind</a>, "<code>S(n,k)</code>", the number of |
| ways of partitioning an <code>n</code>-element set into <code>k</code> non-empty |
| subsets. |
| <p> |
| The preconditions are <code>0 <= k <= n </code> (otherwise |
| <code>NotPositiveException</code> is thrown) |
| </p></div> |
| <dl><dt><span class="strong">Parameters:</span></dt><dd><code>n</code> - the size of the set</dd><dd><code>k</code> - the number of non-empty subsets</dd> |
| <dt><span class="strong">Returns:</span></dt><dd><code>S(n,k)</code></dd> |
| <dt><span class="strong">Throws:</span></dt> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></code> - if <code>k < 0</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>k > n</code>.</dd> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/MathArithmeticException.html" title="class in org.apache.commons.math3.exception">MathArithmeticException</a></code> - if some overflow happens, typically for n exceeding 25 and |
| k between 20 and n-2 (S(n,n-1) is handled specifically and does not overflow)</dd><dt><span class="strong">Since:</span></dt> |
| <dd>3.1</dd></dl> |
| </li> |
| </ul> |
| <a name="combinationsIterator(int, int)"> |
| <!-- --> |
| </a> |
| <ul class="blockList"> |
| <li class="blockList"> |
| <h4>combinationsIterator</h4> |
| <pre>public static <a href="http://docs.oracle.com/javase/6/docs/api/java/util/Iterator.html?is-external=true" title="class or interface in java.util">Iterator</a><int[]> combinationsIterator(int n, |
| int k)</pre> |
| <div class="block">Returns an iterator whose range is the k-element subsets of {0, ..., n - 1} |
| represented as <code>int[]</code> arrays. |
| <p> |
| The arrays returned by the iterator are sorted in descending order and |
| they are visited in lexicographic order with significance from right to |
| left. For example, combinationsIterator(4, 2) returns an Iterator that |
| will generate the following sequence of arrays on successive calls to |
| <code>next()</code>:<br/> |
| <code>[0, 1], [0, 2], [1, 2], [0, 3], [1, 3], [2, 3]</code> |
| </p> |
| If <code>k == 0</code> an Iterator containing an empty array is returned and |
| if <code>k == n</code> an Iterator containing [0, ..., n -1] is returned.</div> |
| <dl><dt><span class="strong">Parameters:</span></dt><dd><code>n</code> - Size of the set from which subsets are selected.</dd><dd><code>k</code> - Size of the subsets to be enumerated.</dd> |
| <dt><span class="strong">Returns:</span></dt><dd>an <a href="http://docs.oracle.com/javase/6/docs/api/java/util/Iterator.html?is-external=true" title="class or interface in java.util"><code>iterator</code></a> over the k-sets in n.</dd> |
| <dt><span class="strong">Throws:</span></dt> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></code> - if <code>n < 0</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>k > n</code>.</dd></dl> |
| </li> |
| </ul> |
| <a name="checkBinomial(int, int)"> |
| <!-- --> |
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| <h4>checkBinomial</h4> |
| <pre>public static void checkBinomial(int n, |
| int k) |
| throws <a href="../../../../../org/apache/commons/math3/exception/NumberIsTooLargeException.html" title="class in org.apache.commons.math3.exception">NumberIsTooLargeException</a>, |
| <a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></pre> |
| <div class="block">Check binomial preconditions.</div> |
| <dl><dt><span class="strong">Parameters:</span></dt><dd><code>n</code> - Size of the set.</dd><dd><code>k</code> - Size of the subsets to be counted.</dd> |
| <dt><span class="strong">Throws:</span></dt> |
| <dd><code><a href="../../../../../org/apache/commons/math3/exception/NotPositiveException.html" title="class in org.apache.commons.math3.exception">NotPositiveException</a></code> - if <code>n < 0</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>k > n</code>.</dd></dl> |
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