From 85132716d335a05bb35f8bb48c65d1c6dce934d3 Mon Sep 17 00:00:00 2001 From: "jan.reininghaus" Date: Mon, 24 Jun 2013 09:48:27 +0000 Subject: new block_spectral_sequence_reduction git-svn-id: https://phat.googlecode.com/svn/trunk@134 8e3bb3c2-eed4-f18f-5264-0b6c94e6926d --- .../algorithms/block_spectral_sequence_reduction.h | 79 ++++++++++++++++++++++ 1 file changed, 79 insertions(+) create mode 100644 include/phat/algorithms/block_spectral_sequence_reduction.h (limited to 'include') diff --git a/include/phat/algorithms/block_spectral_sequence_reduction.h b/include/phat/algorithms/block_spectral_sequence_reduction.h new file mode 100644 index 0000000..398236e --- /dev/null +++ b/include/phat/algorithms/block_spectral_sequence_reduction.h @@ -0,0 +1,79 @@ +/* Copyright 2013 IST Austria + Contributed by: Jan Reininghaus + + This file is part of PHAT. + + PHAT is free software: you can 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 3 of the License, or + (at your option) any later version. + + PHAT is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with PHAT. If not, see . */ + +#pragma once + +#include +#include + +namespace phat { + class block_spectral_sequence_reduction { + public: + template< typename Representation > + void operator () ( boundary_matrix< Representation >& boundary_matrix ) { + + const index nr_columns = boundary_matrix.get_num_cols(); + std::vector< index > lowest_one_lookup( nr_columns, -1 ); + + //const index num_stripes = sqrt( nr_columns ); + const index num_stripes = omp_get_max_threads(); + + index block_size = ( nr_columns % num_stripes == 0 ) ? nr_columns / num_stripes : block_size = nr_columns / num_stripes + 1; + + std::vector< std::vector< index > > unreduced_cols_cur_pass( num_stripes ); + std::vector< std::vector< index > > unreduced_cols_next_pass( num_stripes ); + + for( index cur_dim = boundary_matrix.get_max_dim(); cur_dim >= 1 ; cur_dim-- ) { + #pragma omp parallel for schedule( guided, 1 ) + for( index cur_stripe = 0; cur_stripe < num_stripes; cur_stripe++ ) { + index col_begin = cur_stripe * block_size; + index col_end = std::min( (cur_stripe+1) * block_size, nr_columns ); + for( index cur_col = col_begin; cur_col < col_end; cur_col++ ) + if( boundary_matrix.get_dim( cur_col ) == cur_dim && boundary_matrix.get_max_index( cur_col ) != -1 ) + unreduced_cols_cur_pass[ cur_stripe ].push_back( cur_col ); + } + for( index cur_pass = 0; cur_pass < num_stripes; cur_pass++ ) { + boundary_matrix.sync(); + #pragma omp parallel for schedule( guided, 1 ) + for( int cur_stripe = 0; cur_stripe < num_stripes; cur_stripe++ ) { + index row_begin = (cur_stripe - cur_pass) * block_size; + index row_end = row_begin + block_size; + unreduced_cols_next_pass[ cur_stripe ].clear(); + for( index idx = 0; idx < unreduced_cols_cur_pass[ cur_stripe ].size(); idx++ ) { + index cur_col = unreduced_cols_cur_pass[ cur_stripe ][ idx ]; + index lowest_one = boundary_matrix.get_max_index( cur_col ); + while( lowest_one != -1 && lowest_one >= row_begin && lowest_one < row_end && lowest_one_lookup[ lowest_one ] != -1 ) { + boundary_matrix.add_to( lowest_one_lookup[ lowest_one ], cur_col ); + lowest_one = boundary_matrix.get_max_index( cur_col ); + } + if( lowest_one != -1 ) { + if( lowest_one >= row_begin && lowest_one < row_end ) { + lowest_one_lookup[ lowest_one ] = cur_col; + boundary_matrix.clear( lowest_one ); + } else { + unreduced_cols_next_pass[ cur_stripe ].push_back( cur_col ); + } + } + } + unreduced_cols_next_pass[ cur_stripe ].swap( unreduced_cols_cur_pass[ cur_stripe ] ); + } + } + } + } + }; +} -- cgit v1.2.3