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---------------------------------------------------------------------
//
// Copyright (C) 2009 - 2016 by the deal.II authors
//
// This file is part of the deal.II library.
//
// The deal.II library is free software; you can use it, redistribute
// it, and/or modify it under the terms of the GNU Lesser General
// Public License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
// The full text of the license can be found in the file LICENSE at
// the top level of the deal.II distribution.
//
// ---------------------------------------------------------------------
#ifndef dealii__index_set_h
#define dealii__index_set_h
#include <deal.II/base/config.h>
#include <deal.II/base/utilities.h>
#include <deal.II/base/exceptions.h>
#include <boost/serialization/vector.hpp>
#include <vector>
#include <algorithm>
#ifdef DEAL_II_WITH_TRILINOS
# include <Epetra_Map.h>
#endif
#if defined(DEAL_II_WITH_MPI) || defined(DEAL_II_WITH_PETSC)
#include <mpi.h>
#else
typedef int MPI_Comm;
# ifndef MPI_COMM_WORLD
# define MPI_COMM_WORLD 0
# endif
#endif
DEAL_II_NAMESPACE_OPEN
/**
* A class that represents a subset of indices among a larger set. For
* example, it can be used to denote the set of degrees of freedom within the
* range $[0,\text{dof\_handler.n\_dofs})$ that belongs to a particular
* subdomain, or those among all degrees of freedom that are stored on a
* particular processor in a distributed parallel computation.
*
* This class can represent a collection of half-open ranges of indices as
* well as individual elements. For practical purposes it also stores the
* overall range these indices can assume. In other words, you need to specify
* the size of the index space $[0,\text{size})$ of which objects of this
* class are a subset.
*
* There are two ways to iterate over the IndexSets: First, begin() and end()
* allow iteration over individual indices in the set. Second,
* begin_interval() and end_interval() allow iteration over the half-open
* ranges as described above.
*
* The data structures used in this class along with a rationale can be found
* in the
* @ref distributed_paper "Distributed Computing paper".
*
* @author Wolfgang Bangerth, 2009
*/
class IndexSet
{
public:
// forward declarations:
class ElementIterator;
class IntervalIterator;
/**
* @p size_type is the type used for storing the size and the individual
* entries in the IndexSet.
*/
typedef types::global_dof_index size_type;
/**
* One can see an IndexSet as a container of size size(), where the elements
* of the containers are bool values that are either false or true,
* depending on whether a particular index is an element of the IndexSet or
* not. In other words, an IndexSet is a bit like a vector in which the
* elements we store are booleans. In this view, the correct local typedef
* indicating the type of the elements of the vector would then be @p bool.
*
* On the other hand, @p bool has the disadvantage that it is not a
* numerical type that, for example, allows multiplication with a @p double.
* In other words, one can not easily use a vector of booleans in a place
* where other vectors are allowed. Consequently, we declare the type of the
* elements of such a vector as a signed integer. This uses the fact that in
* the C++ language, booleans are implicitly convertible to integers. In
* other words, declaring the type of the elements of the vector as a signed
* integer is only a small lie, but it is a useful one.
*/
typedef signed int value_type;
/**
* Default constructor.
*/
IndexSet ();
/**
* Constructor that also sets the overall size of the index range.
*/
explicit IndexSet (const size_type size);
#ifdef DEAL_II_WITH_TRILINOS
/**
* Constructor from a trilinos Epetra_Map.
*/
explicit IndexSet(const Epetra_Map &map);
#endif
/**
* Remove all indices from this index set. The index set retains its size,
* however.
*/
void clear ();
/**
* Set the maximal size of the indices upon which this object operates.
*
* This function can only be called if the index set does not yet contain
* any elements. This can be achieved by calling clear(), for example.
*/
void set_size (const size_type size);
/**
* Return the size of the index space of which this index set is a subset
* of.
*
* Note that the result is not equal to the number of indices within this
* set. The latter information is returned by n_elements().
*/
size_type size () const;
/**
* Add the half-open range $[\text{begin},\text{end})$ to the set of indices
* represented by this class.
* @param[in] begin The first element of the range to be added.
* @param[in] end The past-the-end element of the range to be added.
*/
void add_range (const size_type begin,
const size_type end);
/**
* Add an individual index to the set of indices.
*/
void add_index (const size_type index);
/**
* Add a whole set of indices described by dereferencing every element of
* the iterator range <code>[begin,end)</code>.
*
* @param[in] begin Iterator to the first element of range of indices to be
* added
* @param[in] end The past-the-end iterator for the range of elements to be
* added. @pre The condition <code>begin@<=end</code> needs to be satisfied.
*/
template <typename ForwardIterator>
void add_indices (const ForwardIterator &begin,
const ForwardIterator &end);
/**
* Add the given IndexSet @p other to the current one, constructing the
* union of *this and @p other.
*
* If the @p offset argument is nonzero, then every index in @p other is
* shifted by @p offset before being added to the current index set. This
* allows to construct, for example, one index set from several others that
* are supposed to represent index sets corresponding to different ranges
* (e.g., when constructing the set of nonzero entries of a block vector
* from the sets of nonzero elements of the individual blocks of a vector).
*
* This function will generate an exception if any of the (possibly shifted)
* indices of the @p other index set lie outside the range
* <code>[0,size())</code> represented by the current object.
*/
void add_indices(const IndexSet &other,
const unsigned int offset = 0);
/**
* Return whether the specified index is an element of the index set.
*/
bool is_element (const size_type index) const;
/**
* Return whether the index set stored by this object defines a contiguous
* range. This is true also if no indices are stored at all.
*/
bool is_contiguous () const;
/**
* Return the number of elements stored in this index set.
*/
size_type n_elements () const;
/**
* Return the global index of the local index with number @p local_index
* stored in this index set. @p local_index obviously needs to be less than
* n_elements().
*/
size_type nth_index_in_set (const unsigned int local_index) const;
/**
* Return the how-manyth element of this set (counted in ascending order) @p
* global_index is. @p global_index needs to be less than the size(). This
* function throws an exception if the index @p global_index is not actually
* a member of this index set, i.e. if is_element(global_index) is false.
*/
size_type index_within_set (const size_type global_index) const;
/**
* Each index set can be represented as the union of a number of contiguous
* intervals of indices, where if necessary intervals may only consist of
* individual elements to represent isolated members of the index set.
*
* This function returns the minimal number of such intervals that are
* needed to represent the index set under consideration.
*/
unsigned int n_intervals () const;
/**
* This function returns the local index of the beginning of the largest
* range.
*/
unsigned int largest_range_starting_index() const;
/**
* Compress the internal representation by merging individual elements with
* contiguous ranges, etc. This function does not have any external effect.
*/
void compress () const;
/**
* Comparison for equality of index sets. This operation is only allowed if
* the size of the two sets is the same (though of course they do not have
* to have the same number of indices).
*/
bool operator == (const IndexSet &is) const;
/**
* Comparison for inequality of index sets. This operation is only allowed
* if the size of the two sets is the same (though of course they do not
* have to have the same number of indices).
*/
bool operator != (const IndexSet &is) const;
/**
* Return the intersection of the current index set and the argument given,
* i.e. a set of indices that are elements of both index sets. The two index
* sets must have the same size (though of course they do not have to have
* the same number of indices).
*/
IndexSet operator & (const IndexSet &is) const;
/**
* This command takes an interval <tt>[begin, end)</tt> and returns the
* intersection of the current index set with the interval, shifted to the
* range <tt>[0, end-begin)</tt>.
*
* In other words, the result of this operation is the intersection of the
* set represented by the current object and the interval <tt>[begin,
* end)</tt>, as seen <i>within the interval <tt>[begin, end)</tt></i> by
* shifting the result of the intersection operation to the left by
* <tt>begin</tt>. This corresponds to the notion of a <i>view</i>: The
* interval <tt>[begin, end)</tt> is a <i>window</i> through which we see
* the set represented by the current object.
*/
IndexSet get_view (const size_type begin,
const size_type end) const;
/**
* Removes all elements contained in @p other from this set. In other words,
* if $x$ is the current object and $o$ the argument, then we compute $x
* \leftarrow x \backslash o$.
*/
void subtract_set (const IndexSet &other);
/**
* Fills the given vector with all indices contained in this IndexSet.
*/
void fill_index_vector(std::vector<size_type> &indices) const;
/**
* Fill the given vector with either zero or one elements, providing a
* binary representation of this index set. The given vector is assumed to
* already have the correct size.
*
* The given argument is filled with integer values zero and one, using
* <code>vector.operator[]</code>. Thus, any object that has such an
* operator can be used as long as it allows conversion of integers zero and
* one to elements of the vector. Specifically, this is the case for classes
* Vector, BlockVector, but also std::vector@<bool@>, std::vector@<int@>,
* and std::vector@<double@>.
*/
template <typename VectorType>
void fill_binary_vector (VectorType &vector) const;
/**
* Outputs a text representation of this IndexSet to the given stream. Used
* for testing.
*/
template <class StreamType>
void print(StreamType &out) const;
/**
* Writes the IndexSet into a text based file format, that can be read in
* again using the read() function.
*/
void write(std::ostream &out) const;
/**
* Constructs the IndexSet from a text based representation given by the
* stream @p in written by the write() function.
*/
void read(std::istream &in);
/**
* Writes the IndexSet into a binary, compact representation, that can be
* read in again using the block_read() function.
*/
void block_write(std::ostream &out) const;
/**
* Constructs the IndexSet from a binary representation given by the stream
* @p in written by the write_block() function.
*/
void block_read(std::istream &in);
#ifdef DEAL_II_WITH_TRILINOS
/**
* Given an MPI communicator, create a Trilinos map object that represents a
* distribution of vector elements or matrix rows in which we will locally
* store those elements or rows for which we store the index in the current
* index set, and all the other elements/rows elsewhere on one of the other
* MPI processes.
*
* The last argument only plays a role if the communicator is a parallel
* one, distributing computations across multiple processors. In that case,
* if the last argument is false, then it is assumed that the index sets
* this function is called with on all processors are mutually exclusive but
* together enumerate each index exactly once. In other words, if you call
* this function on two processors, then the index sets this function is
* called with must together have all possible indices from zero to
* size()-1, and no index must appear in both index sets. This corresponds,
* for example, to the case where we want to split the elements of vectors
* into unique subsets to be stored on different processors -- no element
* should be owned by more than one processor, but each element must be
* owned by one.
*
* On the other hand, if the second argument is true, then the index sets
* can be overlapping, and they also do not need to span the whole index
* set. This is a useful operation if we want to create vectors that not
* only contain the locally owned indices, but for example also the elements
* that correspond to degrees of freedom located on ghost cells. Another
* application of this method is to select a subset of the elements of a
* vector, e.g. for extracting only certain solution components.
*/
Epetra_Map make_trilinos_map (const MPI_Comm &communicator = MPI_COMM_WORLD,
const bool overlapping = false) const;
#endif
/**
* Determine an estimate for the memory consumption (in bytes) of this
* object.
*/
std::size_t memory_consumption () const;
DeclException1 (ExcIndexNotPresent, size_type,
<< "The global index " << arg1
<< " is not an element of this set.");
/**
* Write or read the data of this object to or from a stream for the purpose
* of serialization
*/
template <class Archive>
void serialize (Archive &ar, const unsigned int version);
/**
* @name Iterators
* @{
*/
/**
* Dereferencing an IntervalIterator will return a reference to an object of
* this type. It allows access to a contiguous interval $[a,b[$ (also called
* a range) of the IndexSet being iterated over.
*/
class IntervalAccessor
{
public:
/**
* Construct a valid accessor given an IndexSet and the index @p range_idx
* of the range to point to.
*/
IntervalAccessor(const IndexSet *idxset, const size_type range_idx);
/**
* Construct an invalid accessor for the IndexSet.
*/
explicit IntervalAccessor(const IndexSet *idxset);
/**
* Number of elements in this interval.
*/
size_type n_elements() const;
/**
* If true, we are pointing at a valid interval in the IndexSet.
*/
bool is_valid() const;
/**
* Return an iterator pointing at the first index in this interval.
*/
ElementIterator begin() const;
/**
* Return an iterator pointing directly after the last index in this
* interval.
*/
ElementIterator end() const;
/**
* Return the index of the last index in this interval.
*/
size_type last() const;
private:
/**
* Private copy constructor.
*/
IntervalAccessor(const IntervalAccessor &other);
/**
* Private copy operator.
*/
IntervalAccessor &operator = (const IntervalAccessor &other);
/**
* Test for equality, used by IntervalIterator.
*/
bool operator == (const IntervalAccessor &other) const;
/**
* Smaller-than operator, used by IntervalIterator.
*/
bool operator < (const IntervalAccessor &other) const;
/**
* Advance this accessor to point to the next interval in the @p
* index_set.
*/
void advance ();
/**
* Reference to the IndexSet.
*/
const IndexSet *index_set;
/**
* Index into index_set.ranges[]. Set to numbers::invalid_dof_index if
* invalid or the end iterator.
*/
size_type range_idx;
friend class IntervalIterator;
};
/**
* Class that represents an iterator pointing to a contiguous interval
* $[a,b[$ as returned by IndexSet::begin_interval().
*/
class IntervalIterator
{
public:
/**
* Construct a valid iterator pointing to the interval with index @p
* range_idx.
*/
IntervalIterator(const IndexSet *idxset, const size_type range_idx);
/**
* Construct an invalid iterator (used as end()).
*/
explicit IntervalIterator(const IndexSet *idxset);
/**
* Construct an empty iterator.
*/
IntervalIterator();
/**
* Copy constructor from @p other iterator.
*/
IntervalIterator(const IntervalIterator &other);
/**
* Assignment of another iterator.
*/
IntervalIterator &operator = (const IntervalIterator &other);
/**
* Prefix increment.
*/
IntervalIterator &operator++ ();
/**
* Postfix increment.
*/
IntervalIterator operator++ (int);
/**
* Dereferencing operator, returns an IntervalAccessor.
*/
const IntervalAccessor &operator* () const;
/**
* Dereferencing operator, returns a pointer to an IntervalAccessor.
*/
const IntervalAccessor *operator-> () const;
/**
* Comparison.
*/
bool operator == (const IntervalIterator &) const;
/**
* Inverse of <tt>==</tt>.
*/
bool operator != (const IntervalIterator &) const;
/**
* Comparison operator.
*/
bool operator < (const IntervalIterator &) const;
/**
* Return the distance between the current iterator and the argument. The
* distance is given by how many times one has to apply operator++ to the
* current iterator to get the argument (for a positive return value), or
* operator-- (for a negative return value).
*/
int operator - (const IntervalIterator &p) const;
private:
/**
* Accessor that contains what IndexSet and interval we are pointing at.
*/
IntervalAccessor accessor;
};
/**
* Class that represents an iterator pointing to a single element in the
* IndexSet as returned by IndexSet::begin().
*/
class ElementIterator
{
public:
/**
* Construct an iterator pointing to the global index @p index in the
* interval @p range_idx
*/
ElementIterator(const IndexSet *idxset, const size_type range_idx, const size_type index);
/**
* Construct an iterator pointing to the end of the IndexSet.
*/
explicit ElementIterator(const IndexSet *idxset);
/**
* Dereferencing operator. The returned value is the index of the element
* inside the IndexSet.
*/
size_type operator* () const;
/**
* Does this iterator point to an existing element?
*/
bool is_valid () const;
/**
* Prefix increment.
*/
ElementIterator &operator++ ();
/**
* Postfix increment.
*/
ElementIterator operator++ (int);
/**
* Comparison.
*/
bool operator == (const ElementIterator &) const;
/**
* Inverse of <tt>==</tt>.
*/
bool operator != (const ElementIterator &) const;
/**
* Comparison operator.
*/
bool operator < (const ElementIterator &) const;
/**
* Return the distance between the current iterator and the argument. In
* the expression <code>it_left-it_right</code> the distance is given by
* how many times one has to apply operator++ to the right operand @p
* it_right to get the left operand @p it_left (for a positive return
* value), or to @p it_left to get the @p it_right (for a negative return
* value).
*/
std::ptrdiff_t operator - (const ElementIterator &p) const;
private:
/**
* Advance iterator by one.
*/
void advance ();
/**
* The parent IndexSet.
*/
const IndexSet *index_set;
/**
* Index into index_set.ranges.
*/
size_type range_idx;
/**
* The global index this iterator is pointing at.
*/
size_type idx;
};
/**
* Return an iterator that points at the first index that is contained in
* this IndexSet.
*/
ElementIterator begin() const;
/**
* Return an iterator that points one after the last index that is contained
* in this IndexSet.
*/
ElementIterator end() const;
/**
* Return an Iterator that points at the first interval of this IndexSet.
*/
IntervalIterator begin_intervals() const;
/**
* Return an Iterator that points one after the last interval of this
* IndexSet.
*/
IntervalIterator end_intervals() const;
/**
* @}
*/
private:
/**
* A type that denotes the half open index range <code>[begin,end)</code>.
*
* The nth_index_in_set denotes the how many-th index within this IndexSet
* the first element of the current range is. This information is only
* accurate if IndexSet::compress() has been called after the last
* insertion.
*/
struct Range
{
size_type begin;
size_type end;
size_type nth_index_in_set;
/**
* Default constructor. Since there is no useful choice for a default
* constructed interval, this constructor simply creates something that
* resembles an invalid range. We need this constructor for serialization
* purposes, but the invalid range should be filled with something read
* from the archive before it is used, so we should hopefully never get to
* see an invalid range in the wild.
*/
Range ();
/**
* Constructor. Create a half-open interval with the given indices.
*
* @param i1 Left end point of the interval.
* @param i2 First index greater than the last index of the indicated
* range.
*/
Range (const size_type i1,
const size_type i2);
friend
inline bool operator< (const Range &range_1,
const Range &range_2)
{
return ((range_1.begin < range_2.begin)
||
((range_1.begin == range_2.begin)
&&
(range_1.end < range_2.end)));
}
static bool end_compare(const IndexSet::Range &x, const IndexSet::Range &y)
{
return x.end < y.end;
}
static bool nth_index_compare (const IndexSet::Range &x,
const IndexSet::Range &y)
{
return (x.nth_index_in_set+(x.end-x.begin) <
y.nth_index_in_set+(y.end-y.begin));
}
friend
inline bool operator== (const Range &range_1,
const Range &range_2)
{
return ((range_1.begin == range_2.begin)
&&
(range_1.end == range_2.end));
}
std::size_t memory_consumption () const
{
return sizeof(Range);
}
/**
* Write or read the data of this object to or from a stream for the
* purpose of serialization
*/
template <class Archive>
void serialize (Archive &ar, const unsigned int version);
};
/**
* A set of contiguous ranges of indices that make up (part of) this index
* set. This variable is always kept sorted.
*
* The variable is marked "mutable" so that it can be changed by compress(),
* though this of course doesn't change anything about the external
* representation of this index set.
*/
mutable std::vector<Range> ranges;
/**
* True if compress() has been called after the last change in the set of
* indices.
*
* The variable is marked "mutable" so that it can be changed by compress(),
* though this of course doesn't change anything about the external
* representation of this index set.
*/
mutable bool is_compressed;
/**
* The overall size of the index range. Elements of this index set have to
* have a smaller number than this value.
*/
size_type index_space_size;
/**
* This integer caches the index of the largest range in @p ranges. This
* gives <tt>O(1)</tt> access to the range with most elements, while general
* access costs <tt>O(log(n_ranges))</tt>. The largest range is needed for
* the methods @p is_element(), @p index_within_set(), @p nth_index_in_set.
* In many applications, the largest range contains most elements (the
* locally owned range), whereas there are only a few other elements
* (ghosts).
*/
mutable size_type largest_range;
/**
* Actually perform the compress() operation.
*/
void do_compress() const;
};
/**
* Create and return an index set of size $N$ that contains every single index
* within this range. In essence, this function returns an index set created
* by
* @code
* IndexSet is (N);
* is.add_range(0, N);
* @endcode
* This function exists so that one can create and initialize index sets that
* are complete in one step, or so one can write code like
* @code
* if (my_index_set == complete_index_set(my_index_set.size())
* ...
* @endcode
*
* @relates IndexSet
*/
inline
IndexSet complete_index_set (const unsigned int N)
{
IndexSet is (N);
is.add_range(0, N);
return is;
}
/* ------------------ inline functions ------------------ */
/* IntervalAccessor */
inline
IndexSet::IntervalAccessor::IntervalAccessor(const IndexSet *idxset, const IndexSet::size_type range_idx)
: index_set(idxset), range_idx(range_idx)
{
Assert(range_idx < idxset->n_intervals(), ExcInternalError("Invalid range index"));
}
inline
IndexSet::IntervalAccessor::IntervalAccessor(const IndexSet *idxset)
: index_set(idxset), range_idx(numbers::invalid_dof_index)
{}
inline
IndexSet::size_type IndexSet::IntervalAccessor::n_elements() const
{
Assert(is_valid(), ExcMessage("invalid iterator"));
return index_set->ranges[range_idx].end - index_set->ranges[range_idx].begin;
}
inline
bool IndexSet::IntervalAccessor::is_valid() const
{
return index_set != NULL && range_idx < index_set->n_intervals();
}
inline
IndexSet::ElementIterator IndexSet::IntervalAccessor::begin() const
{
Assert(is_valid(), ExcMessage("invalid iterator"));
return IndexSet::ElementIterator(index_set, range_idx, index_set->ranges[range_idx].begin);
}
inline
IndexSet::ElementIterator IndexSet::IntervalAccessor::end() const
{
Assert(is_valid(), ExcMessage("invalid iterator"));
// point to first index in next interval unless we are the last interval.
if (range_idx < index_set->ranges.size()-1)
return IndexSet::ElementIterator(index_set, range_idx+1, index_set->ranges[range_idx+1].begin);
else
return index_set->end();
}
inline
IndexSet::size_type
IndexSet::IntervalAccessor::last() const
{
Assert(is_valid(), ExcMessage("invalid iterator"));
return index_set->ranges[range_idx].end-1;
}
inline
IndexSet::IntervalAccessor::IntervalAccessor(const IndexSet::IntervalAccessor &other)
: index_set (other.index_set), range_idx(other.range_idx)
{
Assert( range_idx == numbers::invalid_dof_index || is_valid(), ExcMessage("invalid iterator"));
}
inline
IndexSet::IntervalAccessor &
IndexSet::IntervalAccessor::operator = (const IndexSet::IntervalAccessor &other)
{
index_set = other.index_set;
range_idx = other.range_idx;
Assert( range_idx == numbers::invalid_dof_index || is_valid(), ExcMessage("invalid iterator"));
return *this;
}
inline
bool IndexSet::IntervalAccessor::operator == (const IndexSet::IntervalAccessor &other) const
{
Assert (index_set == other.index_set, ExcMessage("Can not compare accessors pointing to different IndexSets"));
return range_idx == other.range_idx;
}
inline
bool IndexSet::IntervalAccessor::operator < (const IndexSet::IntervalAccessor &other) const
{
Assert (index_set == other.index_set, ExcMessage("Can not compare accessors pointing to different IndexSets"));
return range_idx < other.range_idx;
}
inline
void IndexSet::IntervalAccessor::advance ()
{
Assert(is_valid(), ExcMessage("Impossible to advance an IndexSet::IntervalIterator that is invalid"));
++range_idx;
// set ourselves to invalid if we walk off the end
if (range_idx>=index_set->ranges.size())
range_idx = numbers::invalid_dof_index;
}
/* IntervalIterator */
inline
IndexSet::IntervalIterator::IntervalIterator(const IndexSet *idxset, const IndexSet::size_type range_idx)
: accessor(idxset, range_idx)
{}
inline
IndexSet::IntervalIterator::IntervalIterator()
: accessor(NULL)
{}
inline
IndexSet::IntervalIterator::IntervalIterator(const IndexSet *idxset)
: accessor(idxset)
{}
inline
IndexSet::IntervalIterator::IntervalIterator(const IndexSet::IntervalIterator &other)
: accessor(other.accessor)
{}
inline
IndexSet::IntervalIterator &
IndexSet::IntervalIterator::operator = (const IntervalIterator &other)
{
accessor = other.accessor;
return *this;
}
inline
IndexSet::IntervalIterator &
IndexSet::IntervalIterator::operator++ ()
{
accessor.advance();
return *this;
}
inline
IndexSet::IntervalIterator
IndexSet::IntervalIterator::operator++ (int)
{
const IndexSet::IntervalIterator iter = *this;
accessor.advance ();
return iter;
}
inline
const IndexSet::IntervalAccessor &
IndexSet::IntervalIterator::operator* () const
{
return accessor;
}
inline
const IndexSet::IntervalAccessor *
IndexSet::IntervalIterator::operator-> () const
{
return &accessor;
}
inline
bool IndexSet::IntervalIterator::operator == (const IndexSet::IntervalIterator &other) const
{
return accessor == other.accessor;
}
inline
bool IndexSet::IntervalIterator::operator != (const IndexSet::IntervalIterator &other) const
{
return !(*this == other);
}
inline
bool IndexSet::IntervalIterator::operator < (const IndexSet::IntervalIterator &other) const
{
return accessor < other.accessor;
}
inline
int IndexSet::IntervalIterator::operator - (const IndexSet::IntervalIterator &other) const
{
Assert (accessor.index_set == other.accessor.index_set, ExcMessage("Can not compare iterators belonging to different IndexSets"));
const size_type lhs = (accessor.range_idx == numbers::invalid_dof_index) ? accessor.index_set->ranges.size() : accessor.range_idx;
const size_type rhs = (other.accessor.range_idx == numbers::invalid_dof_index) ? accessor.index_set->ranges.size() : other.accessor.range_idx;
if (lhs > rhs)
return static_cast<int>(lhs - rhs);
else
return -static_cast<int>(rhs - lhs);
}
/* ElementIterator */
inline
bool IndexSet::ElementIterator::is_valid() const
{
Assert(
(range_idx == numbers::invalid_dof_index && idx == numbers::invalid_dof_index)
||
(range_idx < index_set->ranges.size() && idx<index_set->ranges[range_idx].end)
, ExcInternalError("Invalid ElementIterator state."));
return range_idx < index_set->ranges.size() && idx<index_set->ranges[range_idx].end;
}
inline
IndexSet::ElementIterator::ElementIterator(const IndexSet *idxset, const IndexSet::size_type range_idx, const IndexSet::size_type index)
: index_set(idxset), range_idx(range_idx), idx(index)
{
Assert(range_idx < index_set->ranges.size(),
ExcMessage("Invalid range index for IndexSet::ElementIterator constructor."));
Assert(idx >= index_set->ranges[range_idx].begin
&&
idx < index_set->ranges[range_idx].end,
ExcInternalError("Invalid index argument for IndexSet::ElementIterator constructor."));
}
inline
IndexSet::ElementIterator::ElementIterator(const IndexSet *idxset)
: index_set(idxset), range_idx(numbers::invalid_dof_index), idx(numbers::invalid_dof_index)
{}
inline
IndexSet::size_type
IndexSet::ElementIterator::operator* () const
{
Assert(is_valid(), ExcMessage("Impossible to dereference an IndexSet::ElementIterator that is invalid"));
return idx;
}
inline
bool IndexSet::ElementIterator::operator == (const IndexSet::ElementIterator &other) const
{
Assert (index_set == other.index_set, ExcMessage("Can not compare iterators belonging to different IndexSets"));
return range_idx == other.range_idx && idx==other.idx;
}
inline
void IndexSet::ElementIterator::advance ()
{
Assert(is_valid(), ExcMessage("Impossible to advance an IndexSet::ElementIterator that is invalid"));
if (idx < index_set->ranges[range_idx].end)
++idx;
// end of this range?
if (idx == index_set->ranges[range_idx].end)
{
// point to first element in next interval if possible
if (range_idx < index_set->ranges.size()-1)
{
++range_idx;
idx = index_set->ranges[range_idx].begin;
}
else
{
// we just fell off the end, set to invalid:
range_idx = numbers::invalid_dof_index;
idx = numbers::invalid_dof_index;
}
}
}
inline
IndexSet::ElementIterator &
IndexSet::ElementIterator::operator++ ()
{
advance();
return *this;
}
inline
IndexSet::ElementIterator
IndexSet::ElementIterator::operator++ (int)
{
IndexSet::ElementIterator it = *this;
advance();
return it;
}
inline
bool IndexSet::ElementIterator::operator != (const IndexSet::ElementIterator &other) const
{
return !(*this == other);
}
inline
bool IndexSet::ElementIterator::operator < (const IndexSet::ElementIterator &other) const
{
Assert (index_set == other.index_set, ExcMessage("Can not compare iterators belonging to different IndexSets"));
return range_idx < other.range_idx || (range_idx == other.range_idx && idx<other.idx);
}
inline
std::ptrdiff_t IndexSet::ElementIterator::operator - (const IndexSet::ElementIterator &other) const
{
Assert (index_set == other.index_set, ExcMessage("Can not compare iterators belonging to different IndexSets"));
if (*this == other)
return 0;
if (!(*this < other))
return -(other-*this);
// only other can be equal to end() because of the checks above.
Assert (is_valid(), ExcInternalError());
// Note: we now compute how far advance *this in "*this < other" to get other, so we need to return -c at the end.
// first finish the current range:
std::ptrdiff_t c = index_set->ranges[range_idx].end-idx;
// now walk in steps of ranges (need to start one behind our current one):
for (size_type range=range_idx+1; range<index_set->ranges.size() && range<=other.range_idx; ++range)
c += index_set->ranges[range].end-index_set->ranges[range].begin;
Assert(other.range_idx < index_set->ranges.size() || other.range_idx == numbers::invalid_dof_index,
ExcMessage("Inconsistent iterator state. Did you invalidate iterators by modifying the IndexSet?"));
// We might have walked too far because we went until the end of other.range_idx, so walk backwards to other.idx:
if (other.range_idx != numbers::invalid_dof_index)
c -= index_set->ranges[other.range_idx].end - other.idx;
return -c;
}
/* Range */
inline
IndexSet::Range::Range ()
:
begin(numbers::invalid_dof_index),
end(numbers::invalid_dof_index)
{}
inline
IndexSet::Range::Range (const size_type i1,
const size_type i2)
:
begin(i1),
end(i2)
{}
/* IndexSet itself */
inline
IndexSet::ElementIterator IndexSet::begin() const
{
compress();
if (ranges.size()>0)
return IndexSet::ElementIterator(this, 0, ranges[0].begin);
else
return end();
}
inline
IndexSet::ElementIterator IndexSet::end() const
{
compress();
return IndexSet::ElementIterator(this);
}
inline
IndexSet::IntervalIterator IndexSet::begin_intervals() const
{
compress();
if (ranges.size()>0)
return IndexSet::IntervalIterator(this, 0);
else
return end_intervals();
}
inline
IndexSet::IntervalIterator IndexSet::end_intervals() const
{
compress();
return IndexSet::IntervalIterator(this);
}
inline
IndexSet::IndexSet ()
:
is_compressed (true),
index_space_size (0),
largest_range (numbers::invalid_unsigned_int)
{}
inline
IndexSet::IndexSet (const size_type size)
:
is_compressed (true),
index_space_size (size),
largest_range (numbers::invalid_unsigned_int)
{}
inline
void
IndexSet::clear ()
{
ranges.clear ();
largest_range = 0;
is_compressed = true;
}
inline
void
IndexSet::set_size (const size_type sz)
{
Assert (ranges.empty(),
ExcMessage ("This function can only be called if the current "
"object does not yet contain any elements."));
index_space_size = sz;
is_compressed = true;
}
inline
IndexSet::size_type
IndexSet::size () const
{
return index_space_size;
}
inline
void
IndexSet::compress () const
{
if (is_compressed == true)
return;
do_compress();
}
inline
void
IndexSet::add_index (const size_type index)
{
Assert (index < index_space_size,
ExcIndexRangeType<size_type> (index, 0, index_space_size));
const Range new_range(index, index+1);
if (ranges.size() == 0 || index > ranges.back().end)
ranges.push_back(new_range);
else if (index == ranges.back().end)
ranges.back().end++;
else
ranges.insert (Utilities::lower_bound (ranges.begin(),
ranges.end(),
new_range),
new_range);
is_compressed = false;
}
template <typename ForwardIterator>
inline
void
IndexSet::add_indices (const ForwardIterator &begin,
const ForwardIterator &end)
{
// insert each element of the range. if some of them happen to be
// consecutive, merge them to a range
for (ForwardIterator p=begin; p!=end;)
{
const size_type begin_index = *p;
size_type end_index = begin_index + 1;
ForwardIterator q = p;
++q;
while ((q != end) && (*q == end_index))
{
++end_index;
++q;
}
add_range (begin_index, end_index);
p = q;
}
}
inline
bool
IndexSet::is_element (const size_type index) const
{
if (ranges.empty() == false)
{
compress ();
// fast check whether the index is in the largest range
Assert (largest_range < ranges.size(), ExcInternalError());
if (index >= ranges[largest_range].begin &&
index < ranges[largest_range].end)
return true;
// get the element after which we would have to insert a range that
// consists of all elements from this element to the end of the index
// range plus one. after this call we know that if p!=end() then
// p->begin<=index unless there is no such range at all
//
// if the searched for element is an element of this range, then we're
// done. otherwise, the element can't be in one of the following ranges
// because otherwise p would be a different iterator
//
// since we already know the position relative to the largest range (we
// called compress!), we can perform the binary search on ranges with
// lower/higher number compared to the largest range
std::vector<Range>::const_iterator
p = std::upper_bound (ranges.begin() + (index<ranges[largest_range].begin?
0 : largest_range+1),
index<ranges[largest_range].begin ?
ranges.begin() + largest_range:
ranges.end(),
Range (index, size()+1));
if (p == ranges.begin())
return ((index >= p->begin) && (index < p->end));
Assert ((p == ranges.end()) || (p->begin > index),
ExcInternalError());
// now move to that previous range
--p;
Assert (p->begin <= index, ExcInternalError());
return (p->end > index);
}
// didn't find this index, so it's not in the set
return false;
}
inline
bool
IndexSet::is_contiguous () const
{
compress ();
return (ranges.size() <= 1);
}
inline
IndexSet::size_type
IndexSet::n_elements () const
{
// make sure we have non-overlapping ranges
compress ();
size_type v = 0;
if (!ranges.empty())
{
Range &r = ranges.back();
v = r.nth_index_in_set + r.end - r.begin;
}
#ifdef DEBUG
size_type s = 0;
for (std::vector<Range>::iterator range = ranges.begin();
range != ranges.end();
++range)
s += (range->end - range->begin);
Assert(s==v, ExcInternalError());
#endif
return v;
}
inline
unsigned int
IndexSet::n_intervals () const
{
compress ();
return ranges.size();
}
inline
unsigned int
IndexSet::largest_range_starting_index() const
{
Assert(ranges.empty()==false, ExcMessage("IndexSet cannot be empty."));
compress();
const std::vector<Range>::const_iterator main_range=ranges.begin()+largest_range;
return main_range->nth_index_in_set;
}
inline
IndexSet::size_type
IndexSet::nth_index_in_set (const unsigned int n) const
{
// to make this call thread-safe, compress() must not be called through this
// function
Assert (is_compressed == true, ExcMessage ("IndexSet must be compressed."));
Assert (n < n_elements(), ExcIndexRangeType<size_type> (n, 0, n_elements()));
// first check whether the index is in the largest range
Assert (largest_range < ranges.size(), ExcInternalError());
std::vector<Range>::const_iterator main_range=ranges.begin()+largest_range;
if (n>=main_range->nth_index_in_set &&
n<main_range->nth_index_in_set+(main_range->end-main_range->begin))
return main_range->begin + (n-main_range->nth_index_in_set);
// find out which chunk the local index n belongs to by using a binary
// search. the comparator is based on the end of the ranges. Use the
// position relative to main_range to subdivide the ranges
Range r (n,n+1);
r.nth_index_in_set = n;
std::vector<Range>::const_iterator range_begin, range_end;
if (n<main_range->nth_index_in_set)
{
range_begin = ranges.begin();
range_end = main_range;
}
else
{
range_begin = main_range + 1;
range_end = ranges.end();
}
const std::vector<Range>::const_iterator
p = Utilities::lower_bound(range_begin, range_end, r,
Range::nth_index_compare);
Assert (p != ranges.end(), ExcInternalError());
return p->begin + (n-p->nth_index_in_set);
}
inline
IndexSet::size_type
IndexSet::index_within_set (const size_type n) const
{
// to make this call thread-safe, compress() must not be called through this
// function
Assert (is_compressed == true, ExcMessage ("IndexSet must be compressed."));
Assert (is_element(n) == true, ExcIndexNotPresent (n));
Assert (n < size(), ExcIndexRangeType<size_type> (n, 0, size()));
// check whether the index is in the largest range. use the result to
// perform a one-sided binary search afterward
Assert (largest_range < ranges.size(), ExcInternalError());
std::vector<Range>::const_iterator main_range=ranges.begin()+largest_range;
if (n >= main_range->begin && n < main_range->end)
return (n-main_range->begin) + main_range->nth_index_in_set;
Range r(n, n);
std::vector<Range>::const_iterator range_begin, range_end;
if (n<main_range->begin)
{
range_begin = ranges.begin();
range_end = main_range;
}
else
{
range_begin = main_range + 1;
range_end = ranges.end();
}
std::vector<Range>::const_iterator
p = Utilities::lower_bound(range_begin, range_end, r,
Range::end_compare);
Assert(p!=ranges.end(), ExcInternalError());
Assert(p->begin<=n, ExcInternalError());
Assert(n<p->end, ExcInternalError());
return (n-p->begin) + p->nth_index_in_set;
}
inline
bool
IndexSet::operator == (const IndexSet &is) const
{
Assert (size() == is.size(),
ExcDimensionMismatch (size(), is.size()));
compress ();
is.compress ();
return ranges == is.ranges;
}
inline
bool
IndexSet::operator != (const IndexSet &is) const
{
Assert (size() == is.size(),
ExcDimensionMismatch (size(), is.size()));
compress ();
is.compress ();
return ranges != is.ranges;
}
template <typename Vector>
void
IndexSet::fill_binary_vector (Vector &vector) const
{
Assert (vector.size() == size(),
ExcDimensionMismatch (vector.size(), size()));
compress();
// first fill all elements of the vector with zeroes.
std::fill (vector.begin(), vector.end(), 0);
// then write ones into the elements whose indices are contained in the
// index set
for (std::vector<Range>::iterator it = ranges.begin();
it != ranges.end();
++it)
for (size_type i=it->begin; i<it->end; ++i)
vector[i] = 1;
}
template <class StreamType>
inline
void
IndexSet::print (StreamType &out) const
{
compress();
out << "{";
std::vector<Range>::const_iterator p;
for (p = ranges.begin(); p != ranges.end(); ++p)
{
if (p->end-p->begin==1)
out << p->begin;
else
out << "[" << p->begin << "," << p->end-1 << "]";
if (p !=--ranges.end())
out << ", ";
}
out << "}" << std::endl;
}
template <class Archive>
inline
void
IndexSet::Range::serialize (Archive &ar, const unsigned int)
{
ar &begin &end &nth_index_in_set;
}
template <class Archive>
inline
void
IndexSet::serialize (Archive &ar, const unsigned int)
{
ar &ranges &is_compressed &index_space_size &largest_range;
}
DEAL_II_NAMESPACE_CLOSE
#endif
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