Partitions-class

$,Partitions-method

The <code>Partitions</code> class is an S4-class that exposes C++ classes that provide access to iterators and other useful methods.

classes

iterator

partitions

integer

combinatorics

Provides optimized functions and flexible iterators implemented in
C++ for solving problems in combinatorics and computational mathematics.
Handles various combinatorial objects including combinations, permutations,
integer partitions and compositions, Cartesian products, unordered
Cartesian products, and partition of groups. Utilizes the RMatrix class
from 'RcppParallel' for thread safety. The combination and permutation
functions contain constraint parameters that allow for generation of all
results of a vector meeting specific criteria (e.g. finding all
combinations such that the sum is between two bounds). Capable of
ranking/unranking combinatorial objects efficiently (e.g. retrieve only the
nth lexicographical result) which sets up nicely for parallelization as
well as random sampling. Gmp support permits exploration where the total
number of results is large (e.g. comboSample(10000, 500, n = 4)).
Additionally, there are several high performance number theoretic
functions that are useful for problems common in computational mathematics.
Some of these functions make use of the fast integer division library
'libdivide'. The primeSieve function is based on the segmented sieve of
Eratosthenes implementation by Kim Walisch. It is also efficient for large
numbers by using the cache friendly improvements originally developed by
Tomás Oliveira. Finally, there is a prime counting function that implements
Legendre's formula based on the work of Kim Walisch.

Joseph Wood

RcppAlgos

High Performance Tools for Combinatorics and Computational
Mathematics

Partitions-class function

<dl>
 <dt><code>nextIter</code></dt>
<dd>Retrieve the next lexicographical result</dd> <dt><code>nextNIter</code></dt>
<dd>Pass an integer n to retrieve the next n lexicographical results</dd> <dt><code>nextRemaining</code></dt>
<dd>Retrieve all remaining lexicographical results</dd> <dt><code>currIter</code></dt>
<dd>Returns the current iteration</dd> <dt><code>startOver</code></dt>
<dd>Resets the iterator</dd> <dt><code>sourceVector</code></dt>
<dd>View the source vector</dd> <dt><code>summary</code></dt>
<dd>Returns a list of summary information about the iterator</dd> <dt><code>front</code></dt>
<dd>Retrieve the first lexicographical result</dd> <dt><code>back</code></dt>
<dd>Retrieve the last lexicographical result</dd> <dt><code>randomAccess</code></dt>
<dd>Random access method. Pass a single value or a vector of valid indices. If a single value is passed, the internal index of the iterator will be updated, however if a vector is passed the internal state will not change. GMP support allows for flexible indexing.</dd> 
</dl>

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S4-class for Exposing C++ Partitions Class — Partitions-class

<dl>
 <dt><code>nextIter</code></dt>
<dd>Retrieve the next lexicographical result</dd>

 <dt><code>nextNIter</code></dt>
<dd>Pass an integer n to retrieve the next n lexicographical results</dd>

 <dt><code>nextRemaining</code></dt>
<dd>Retrieve all remaining lexicographical results</dd>

 <dt><code>currIter</code></dt>
<dd>Returns the current iteration</dd>

 <dt><code>startOver</code></dt>
<dd>Resets the iterator</dd>

 <dt><code>sourceVector</code></dt>
<dd>View the source vector</dd>

 <dt><code>summary</code></dt>
<dd>Returns a list of summary information about the iterator</dd>

 <dt><code>front</code></dt>
<dd>Retrieve the first lexicographical result</dd>

 <dt><code>back</code></dt>
<dd>Retrieve the last lexicographical result</dd>

 <dt><code>randomAccess</code></dt>
<dd>Random access method. Pass a single value or a vector of valid indices. If a single value is passed, the internal index of the iterator will be updated, however if a vector is passed the internal state will not change. GMP support allows for flexible indexing.</dd>

 
</dl>

Partitions-class: S4-class for Exposing C++ Partitions Class

Description

Arguments

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See Also

Examples