BitMagic-C++
rscsample01.cpp

Example of how to use bm::rsc_sparse_vector<> template class

See also
bm::sparse_vector
bm::rsc_sparse_vector
bm::sparse_vector::push_back
bm::sparse_vector_serialize
bm::sparse_vector_deserialize
/*
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 rscsample01.cpp
Example of how to use bm::rsc_sparse_vector<> template class
\sa bm::sparse_vector
\sa bm::rsc_sparse_vector
\sa bm::sparse_vector::push_back
\sa bm::sparse_vector_serialize
\sa bm::sparse_vector_deserialize
*/
/*! \file rscsample01.cpp
\brief Example: rsc_sparse_vector<> usage
rsc_sparse_vector<> is a sparse vector which uses bit-transposition and
rank-select succinct method of compression of NULL (unassigned) values.
Unassigned values are dropped (as transposed columns) from the bit-matrix.
rsc_sparse_vector<> is basically a read-only structure, which can be used
for compact data storage and search. Random access to elements is possible
with a penalty of bit-vector Rank or Select operations.
*/
#include <iostream>
#include <vector>
#include "bm.h"
#include "bmsparsevec.h"
using namespace std;
template<class SV>
void print_svector(const SV& sv, bool show_nulls = false)
{
std::cout << sv.size() << ": ";
for (unsigned i = 0; i < sv.size(); ++i)
{
if (show_nulls)
{
if (sv.is_null(i))
std::cout << "NULL, ";
else
{
typename SV::value_type v = sv.get(i);
std::cout << v << ", ";
}
}
else
{
typename SV::value_type v = sv.get(i);
std::cout << v << ", ";
}
}
std::cout << std::endl;
}
int main(void)
{
// temp buffer to avoid unnecessary re-allocations
try
{
sparse_vector_u32 sv1(bm::use_null); // use null is needed to build rsc vector
// fill in sparse vector leaving some unassigned gaps
for (unsigned i = 0; i < 15; i+=3)
{
sv1[i] = i;
}
print_svector(sv1); // print sparse vector disregard NULL values (printed as 0)
print_svector(sv1, true); // print sparse vector show NULLs (unassigned)
csv2.load_from(sv1); // load rank-select-compacted (rsc) sparse vector
// print results - it should look the same
print_svector(csv2, true);
// serialize rsc vector
// optimize memory allocation of sparse vector
csv2.optimize(tb);
bm::sparse_vector_serialize(csv2, sv_lay, tb);
// memory copy just simulates network or DB transaction
const unsigned char* buf = sv_lay.buf();
size_t buf_size = sv_lay.size();
vector<unsigned char> tmp_buf(buf_size);
::memcpy(&tmp_buf[0], buf, buf_size);
rsc_sparse_vector_u32 csv3; // target vector
int res = bm::sparse_vector_deserialize(csv3, &tmp_buf[0], tb);
if (res != 0)
{
std::cerr << "De-Serialization error!" << std::endl;
return 1;
}
if (!csv3.equal(csv2) )
{
cerr << "Error! Please report a bug to BitMagic project support." << endl;
return 1;
}
// unload rsc to sv, this makes a round-trip to an editable form
csv3.load_to(sv3);
if (!sv3.equal(sv1) )
{
std::cerr << "Error! Please report a bug to BitMagic project support." << std::endl;
return 1;
}
print_svector(sv1, true); // print sparse vector again
}
catch(std::exception& ex)
{
std::cerr << ex.what() << std::endl;
return 1;
}
return 0;
}
bm::rsc_sparse_vector::equal
bool equal(const rsc_sparse_vector< Val, SV > &csv) const BMNOEXCEPT
check if another vector has the same content
Definition: bmsparsevec_compr.h:1033
bm::rsc_sparse_vector::load_to
void load_to(sparse_vector_type &sv) const
Exort compressed vector to a sparse vector (with NULLs)
Definition: bmsparsevec_compr.h:1088
bm::sparse_vector
sparse vector with runtime compression using bit transposition method
Definition: bmsparsevec.h:81
BM_DECLARE_TEMP_BLOCK
#define BM_DECLARE_TEMP_BLOCK(x)
Definition: bm.h:47
bm::sparse_vector_serial_layout::buf
const unsigned char * buf() const
Return serialization buffer pointer.
Definition: bmsparsevec_serial.h:106
bmsparsevec.h
Sparse constainer sparse_vector<> for integer types using bit-transposition transform.
bmsparsevec_serial.h
Serialization for sparse_vector<>
bm::sparse_vector_deserialize
int sparse_vector_deserialize(SV &sv, const unsigned char *buf, bm::word_t *temp_block=0)
Deserialize sparse vector.
Definition: bmsparsevec_serial.h:380
bm::sparse_vector_serialize
void sparse_vector_serialize(const SV &sv, sparse_vector_serial_layout< SV > &sv_layout, bm::word_t *temp_block=0)
Serialize sparse vector into a memory buffer(s) structure.
Definition: bmsparsevec_serial.h:356
bmsparsevec_compr.h
Compressed sparse container rsc_sparse_vector<> for integer types.
bm::sparse_vector_serial_layout
layout class for serialization buffer structure
Definition: bmsparsevec_serial.h:57
bm::use_null
@ use_null
support "non-assigned" or "NULL" logic
Definition: bmconst.h:215
sparse_vector_u32
bm::sparse_vector< unsigned, bm::bvector<> > sparse_vector_u32
Definition: rscsample01.cpp:52
main
int main(void)
Definition: rscsample01.cpp:80
bm::rsc_sparse_vector::load_from
void load_from(const sparse_vector_type &sv_src)
Load compressed vector from a sparse vector (with NULLs)
Definition: bmsparsevec_compr.h:1047
bm::rsc_sparse_vector
Rank-Select compressed sparse vector.
Definition: bmsparsevec_compr.h:58
rsc_sparse_vector_u32
bm::rsc_sparse_vector< unsigned, sparse_vector_u32 > rsc_sparse_vector_u32
Definition: rscsample01.cpp:53
bm::rsc_sparse_vector::optimize
void optimize(bm::word_t *temp_block=0, typename bvector_type::optmode opt_mode=bvector_type::opt_compress, statistics *stat=0)
run memory optimization for all vector plains
Definition: bmsparsevec_compr.h:1239
bm::sparse_vector_serial_layout::size
size_t size() const
return current serialized size
Definition: bmsparsevec_serial.h:84
print_svector
void print_svector(const SV &sv, bool show_nulls=false)
Definition: rscsample01.cpp:56
bm.h
Compressed bit-vector bvector<> container, set algebraic methods, traversal iterators.