text: /*################################################################################
    ##
    ##   Copyright (C) 2011-2020 Keith O'Hara
    ##
    ##   This file is part of the StatsLib C++ library.
    ##
    ##   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.
    ##
    ################################################################################*/
  
  #define TEST_PRINT_PRECISION_1 2
  #define TEST_PRINT_PRECISION_2 5
  
  #include "../stats_tests.hpp"
  
  int main()
  {
      print_begin("dgamma");
  
      // parameters
  
      double shape_par = 2.0;
      double scale_par = 3.0;
  
      //
  
      std::vector<double> inp_vals = { 1.0,         2.0,        3.0 };
      std::vector<double> exp_vals = { 0.07961459,  0.1140927,  0.1226265 };
  
      //
      // scalar tests
  
      STATS_TEST_EXPECTED_VAL(dgamma,inp_vals[0],exp_vals[0],false,shape_par,scale_par);
      STATS_TEST_EXPECTED_VAL(dgamma,inp_vals[1],exp_vals[1],false,shape_par,scale_par);
      STATS_TEST_EXPECTED_VAL(dgamma,inp_vals[2],exp_vals[2],false,shape_par,scale_par);
      STATS_TEST_EXPECTED_VAL(dgamma,inp_vals[1],exp_vals[1],true,shape_par,scale_par);
  
      STATS_TEST_EXPECTED_VAL(dgamma,TEST_NAN,TEST_NAN,false,shape_par,scale_par);                    // NaN inputs
      STATS_TEST_EXPECTED_VAL(dgamma,2,TEST_NAN,false,TEST_NAN,scale_par);
      STATS_TEST_EXPECTED_VAL(dgamma,2,TEST_NAN,false,shape_par,TEST_NAN);
      STATS_TEST_EXPECTED_VAL(dgamma,2,TEST_NAN,false,TEST_NAN,TEST_NAN);
      STATS_TEST_EXPECTED_VAL(dgamma,TEST_NAN,TEST_NAN,false,TEST_NAN,TEST_NAN);
  
      STATS_TEST_EXPECTED_VAL(dgamma,2,TEST_NAN,false,-1,2);                                          // shape < 0
      STATS_TEST_EXPECTED_VAL(dgamma,2,TEST_NAN,false,TEST_NEGINF,2);
  
      STATS_TEST_EXPECTED_VAL(dgamma,2,TEST_NAN,false,1,0);                                           // scale <= 0
      STATS_TEST_EXPECTED_VAL(dgamma,2,TEST_NAN,false,4,-1);
      STATS_TEST_EXPECTED_VAL(dgamma,2,TEST_NAN,false,3,TEST_NEGINF);
  
      STATS_TEST_EXPECTED_VAL(dgamma,-1,0.0,false,shape_par,scale_par);                               // x < 0
      STATS_TEST_EXPECTED_VAL(pgamma,TEST_NEGINF,0.0,false,shape_par,scale_par);
  
      STATS_TEST_EXPECTED_VAL(dgamma,0,TEST_POSINF,false,0,2);                                        // shape == 0
      STATS_TEST_EXPECTED_VAL(dgamma,1,0,false,0,2);
  
      STATS_TEST_EXPECTED_VAL(dgamma,0,TEST_POSINF,false,0.5,3);                                      // x == 0
      STATS_TEST_EXPECTED_VAL(dgamma,0,1/scale_par,false,1,scale_par);
      STATS_TEST_EXPECTED_VAL(dgamma,0,0,false,2,3);
  
      STATS_TEST_EXPECTED_VAL(dgamma,TEST_POSINF,0,false,TEST_POSINF,TEST_POSINF);                    // x == +Inf or shape == +Inf or scale == +Inf
      STATS_TEST_EXPECTED_VAL(dgamma,TEST_POSINF,0,false,2,2);
      STATS_TEST_EXPECTED_VAL(dgamma,2,0,false,TEST_POSINF,2);
      STATS_TEST_EXPECTED_VAL(dgamma,2,0,false,2,TEST_POSINF);
   
      //
      // vector/matrix tests
  
  #ifdef STATS_TEST_STDVEC_FEATURES
      STATS_TEST_EXPECTED_MAT(dgamma,inp_vals,exp_vals,std::vector<double>,false,shape_par,scale_par);
      STATS_TEST_EXPECTED_MAT(dgamma,inp_vals,exp_vals,std::vector<double>,true,shape_par,scale_par);
  #endif
  
  #ifdef STATS_TEST_MATRIX_FEATURES
      mat_obj inp_mat(2,3);
      inp_mat(0,0) = inp_vals[0];
      inp_mat(1,0) = inp_vals[2];
      inp_mat(0,1) = inp_vals[1];
      inp_mat(1,1) = inp_vals[0];
      inp_mat(0,2) = inp_vals[2];
      inp_mat(1,2) = inp_vals[1];
  
      mat_obj exp_mat(2,3);
      exp_mat(0,0) = exp_vals[0];
      exp_mat(1,0) = exp_vals[2];
      exp_mat(0,1) = exp_vals[1];
      exp_mat(1,1) = exp_vals[0];
      exp_mat(0,2) = exp_vals[2];
      exp_mat(1,2) = exp_vals[1];
  
      STATS_TEST_EXPECTED_MAT(dgamma,inp_mat,exp_mat,mat_obj,false,shape_par,scale_par);
      STATS_TEST_EXPECTED_MAT(dgamma,inp_mat,exp_mat,mat_obj,true,shape_par,scale_par);
  #endif
  
      // 
  
      print_final("dgamma");
  
      return 0;
  }
  