1 // -*- mode: C++; c-indent-level: 4; c-basic-offset: 4; indent-tabs-mode: nil; -*- 2 // 3 // rnbinom_mu.h: Rcpp R/C++ interface class library -- 4 // 5 // Copyright (C) 2010 - 2016 Douglas Bates, Dirk Eddelbuettel and Romain Francois 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__stats__random_rnbinom_mu_h 23 #define Rcpp__stats__random_rnbinom_mu_h 24 25 namespace Rcpp { 26 namespace stats { 27 28 class NBinomGenerator_Mu : public ::Rcpp::Generator<double> { 29 public: 30 NBinomGenerator_Mu(double siz_,double mu_)31 NBinomGenerator_Mu( double siz_, double mu_ ) : 32 siz(siz_), lambda( mu_ / siz_ ) {} 33 operator()34 inline double operator()() const { 35 return ::Rf_rpois( ::Rf_rgamma( siz, lambda ) ) ; 36 } 37 38 private: 39 double siz ; 40 double lambda ; 41 }; 42 43 } // stats 44 } // Rcpp 45 46 #endif 47