$search
00001 // Copyright (C) 2009-2010 NICTA (www.nicta.com.au) 00002 // Copyright (C) 2009-2010 Conrad Sanderson 00003 // 00004 // This file is part of the Armadillo C++ library. 00005 // It is provided without any warranty of fitness 00006 // for any purpose. You can redistribute this file 00007 // and/or modify it under the terms of the GNU 00008 // Lesser General Public License (LGPL) as published 00009 // by the Free Software Foundation, either version 3 00010 // of the License or (at your option) any later version. 00011 // (see http://www.opensource.org/licenses for more info) 00012 00013 00016 00017 00018 00019 00020 template<typename T1, typename T2> 00021 struct arma_sort_index_packet_ascend 00022 { 00023 T1 val; 00024 T2 index; 00025 }; 00026 00027 00028 00029 template<typename T1, typename T2> 00030 struct arma_sort_index_packet_descend 00031 { 00032 T1 val; 00033 T2 index; 00034 }; 00035 00036 00037 00038 template<typename T1, typename T2> 00039 inline 00040 bool 00041 operator< (const arma_sort_index_packet_ascend<T1,T2>& A, const arma_sort_index_packet_ascend<T1,T2>& B) 00042 { 00043 return A.val < B.val; 00044 } 00045 00046 00047 00048 template<typename T1, typename T2> 00049 inline 00050 bool 00051 operator< (const arma_sort_index_packet_descend<T1,T2>& A, const arma_sort_index_packet_descend<T1,T2>& B) 00052 { 00053 return A.val > B.val; 00054 } 00055 00056 00057 00058 template<typename umat_elem_type, typename packet_type, typename eT> 00059 void 00060 inline 00061 sort_index_helper(umat_elem_type* out_mem, std::vector<packet_type>& packet_vec, const eT* in_mem) 00062 { 00063 arma_extra_debug_sigprint(); 00064 00065 const uword n_elem = packet_vec.size(); 00066 00067 for(uword i=0; i<n_elem; ++i) 00068 { 00069 packet_vec[i].val = in_mem[i]; 00070 packet_vec[i].index = i; 00071 } 00072 00073 std::sort( packet_vec.begin(), packet_vec.end() ); 00074 00075 for(uword i=0; i<n_elem; ++i) 00076 { 00077 out_mem[i] = packet_vec[i].index; 00078 } 00079 } 00080 00081 00082 00083 template<typename T1> 00084 inline 00085 umat 00086 sort_index(const Base<typename T1::elem_type,T1>& X, const uword sort_type = 0) 00087 { 00088 arma_extra_debug_sigprint(); 00089 00090 typedef typename T1::elem_type eT; 00091 00092 arma_type_check(( is_complex<eT>::value == true )); 00093 00094 const unwrap<T1> tmp(X.get_ref()); 00095 const Mat<eT>& A = tmp.M; 00096 00097 if(A.is_empty() == true) 00098 { 00099 return umat(); 00100 } 00101 00102 arma_debug_check( (A.is_vec() == false), "sort_index(): currently only handles vectors"); 00103 00104 typedef typename umat::elem_type out_elem_type; 00105 00106 umat out(A.n_rows, A.n_cols); 00107 00108 if(sort_type == 0) 00109 { 00110 std::vector< arma_sort_index_packet_ascend<eT,out_elem_type> > packet_vec(A.n_elem); 00111 00112 sort_index_helper(out.memptr(), packet_vec, A.mem); 00113 } 00114 else 00115 { 00116 std::vector< arma_sort_index_packet_descend<eT,out_elem_type> > packet_vec(A.n_elem); 00117 00118 sort_index_helper(out.memptr(), packet_vec, A.mem); 00119 } 00120 00121 return out; 00122 } 00123 00124