1 // -*- mode: C++; c-indent-level: 4; c-basic-offset: 4; indent-tabs-mode: nil; -*- 2 // 3 // one_type.h: Rcpp R/C++ interface class library -- traits functions for eye, ones, zeros 4 // 5 // Copyright (C) 2016 Nathan Russell 6 // 7 // This file is part of Rcpp. 8 // 9 // Rcpp is free software: you can redistribute it and/or modify it 10 // under the terms of the GNU General Public License as published by 11 // the Free Software Foundation, either version 2 of the License, or 12 // (at your option) any later version. 13 // 14 // Rcpp is distributed in the hope that it will be useful, but 15 // WITHOUT ANY WARRANTY; without even the implied warranty of 16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 17 // GNU General Public License for more details. 18 // 19 // You should have received a copy of the GNU General Public License 20 // along with Rcpp. If not, see <http://www.gnu.org/licenses/>. 21 22 #ifndef Rcpp__traits__one_type__h 23 #define Rcpp__traits__one_type__h 24 25 namespace Rcpp { 26 namespace traits { 27 28 template <bool> 29 struct allowed_matrix_type; 30 31 template <> 32 struct allowed_matrix_type<true> {}; 33 34 template <typename T> 35 class one_type { 36 private: 37 Rcomplex op(true_type) const { 38 Rcomplex res; 39 res.i = 0.0; 40 res.r = 1.0; 41 return res; 42 } 43 44 T op(false_type) const { 45 return static_cast<T>(1); 46 } 47 48 public: 49 operator T() const { 50 return op(typename same_type<T, Rcomplex>::type()); 51 } 52 }; 53 54 template <typename T> 55 class zero_type { 56 private: 57 Rcomplex op(true_type) const { 58 Rcomplex res; 59 res.i = 0.0; 60 res.r = 0.0; 61 return res; 62 } 63 64 T op(false_type) const { 65 return static_cast<T>(0); 66 } 67 68 public: 69 operator T() const { 70 return op(typename same_type<T, Rcomplex>::type()); 71 } 72 }; 73 74 } // traits 75 } // Rcpp 76 77 #endif // Rcpp__traits__one_type__h 78 79