BitMagic-C++
sample23.cpp

Example on intervals enumarator.

Example on intervals enumarator.BitMagic bvector<> implements high performance operation on RLE coded bit-vectors, transparently supporting all logical operations like intersections.Serialization uses compressive encoding (binary interpolative codes) to efficiently store collections of intervals.

This example illustrates use of inetrval_enumerator<> to interpret bit-vector as a sequence of 011110 ranges/intervals.

See also
bm::bvector::set_range
bm::interval_enumerator
sample22.cpp
Algorithms for bit intervals
/*
Copyright(c) 2002-2017 Anatoliy Kuznetsov(anatoliy_kuznetsov at yahoo.com)
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
For more information please visit: http://bitmagic.io
*/
/** \example sample23.cpp
Example on intervals enumarator.
BitMagic bvector<> implements high performance operation on RLE
coded bit-vectors, transparently supporting all logical operations
like intersections.Serialization uses compressive encoding
(binary interpolative codes) to efficiently store collections
of intervals.
This example illustrates use of inetrval_enumerator<> to interpret
bit-vector as a sequence of 011110 ranges/intervals.
\sa bm::bvector::set_range
\sa bm::interval_enumerator
\sa sample22.cpp
\sa bvintervals
*/
/*! \file sample23.cpp
\brief Example: interval_enumerator<> - interator class for intervals
*/
#include <iostream>
#include <assert.h>
#include "bm.h"
#include "bmintervals.h"
using namespace std;
int main(void)
{
try
{
bm::bvector<> bv(bm::BM_GAP); // use RLE compressed vector from the start
bv.set_range(10, 10);
bv.set_range(100, 110); // sets a range of 1s [100, 110] .....11111....
bv.set_range(777, 888);
bv.set_range(65536, 65536);
bv.optimize();
{
if (ien.valid())
{
do
{
cout << "[" << ien.start() << ".." << ien.end() << "]";
} while (ien.advance());
cout << endl;
}
}
// case 2: slightly less efficient, but more STL iterator conformant
//
{
// please note prefix increment "++en" is way more efficient
// than possible postfix notation of "ien++" (no temp.copy)
//
for (; ien != ien_end; ++ien)
{
// also uses pair notation to represent interval
cout << "[" << (*ien).first << ".." << (*ien).second << "]";
}
cout << endl;
}
{
// construct enumerator to start from position 102 and
// extend start (to 100)
interval_enumerator_type ien(bv, 102, true);
for (; ien != ien_end; ++ien)
{
cout << "[" << ien.get().first << ".." << ien.get().second << "]";
}
cout << endl;
ien.go_to(105, false); // now re-position enumerator to position 105 without extend start
for (; ien != ien_end; ++ien)
{
cout << "[" << ien.get().first << ".." << ien.get().second << "]";
}
cout << endl;
// now re-position enumerator to position 105 without extend start
ien.go_to(105, false);
for (; ien != ien_end; ++ien)
{
cout << "[" << ien.get().first << ".." << ien.get().second << "]";
}
cout << endl;
// now re-position enumerator to position 115 wit extend start
// target position is not in the interval, so it should find the
// next available one automatically
//
ien.go_to(115, true); // extend_left=true but it should not matter
for (; ien != ien_end; ++ien)
{
cout << "[" << ien.get().first << ".." << ien.get().second << "]";
}
cout << endl;
// go beyond end
ien.go_to(1150000, true);
if (ien.valid())
{
assert(0);
}
else
{
cout << "EMPTY" << endl;
}
}
}
catch(std::exception& ex)
{
std::cerr << ex.what() << std::endl;
return 1;
}
return 0;
}
Compressed bit-vector bvector<> container, set algebraic methods, traversal iterators.
Algorithms for bit ranges and intervals.
Bitvector Bit-vector container with runtime compression of bits.
Definition bm.h:108
void optimize(bm::word_t *temp_block=0, optmode opt_mode=opt_compress, statistics *stat=0)
Optimize memory bitvector's memory allocation.
Definition bm.h:3071
bvector< Alloc > & set_range(size_type left, size_type right, bool value=true)
Sets all bits in the specified closed interval [left,right] Interval must be inside the bvector's siz...
Definition bm.h:2158
forward iterator class to traverse bit-vector as ranges
Definition bmintervals.h:53
const pair_type & get() const BMNOEXCEPT
Get interval pair.
size_type end() const BMNOEXCEPT
Return interval end/right as bit-vector coordinate 011110 [left..right].
bool valid() const BMNOEXCEPT
Returns true if enumerator is valid (false if traversal is done)
size_type start() const BMNOEXCEPT
Return interval start/left as bit-vector coordinate 011110 [left..right].
bool go_to(size_type pos, bool extend_start=true)
Go to inetrval at specified position Jump to position with interval. If interval is not available at ...
@ BM_GAP
GAP compression is ON.
Definition bmconst.h:144
int main(void)
Definition sample1.cpp:38
bm::interval_enumerator< bm::bvector<> > interval_enumerator_type
Definition sample23.cpp:51
Second second
Definition bmfunc.h:124
First first
Definition bmfunc.h:123