.. _program_listing_file_src_primitive.hpp:

Program Listing for File primitive.hpp
======================================

|exhale_lsh| :ref:`Return to documentation for file <file_src_primitive.hpp>` (``src/primitive.hpp``)

.. |exhale_lsh| unicode:: U+021B0 .. UPWARDS ARROW WITH TIP LEFTWARDS

.. code-block:: cpp

   /* This file is part of brille.
   
   Copyright © 2019,2020 Greg Tucker <greg.tucker@stfc.ac.uk>
   
   brille is free software: you can redistribute it and/or modify it under the
   terms of the GNU Affero General Public License as published by the Free
   Software Foundation, either version 3 of the License, or (at your option)
   any later version.
   
   brille 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 Affero General Public License for more details.
   
   You should have received a copy of the GNU Affero General Public License
   along with brille. If not, see <https://www.gnu.org/licenses/>.            */
   
   #ifndef BRILLE_PRIMITIVE_HPP_
   #define BRILLE_PRIMITIVE_HPP_
   #include "spg_database.hpp"
   namespace brille {
   
   template<class T> std::array<T,9> transpose(const std::array<T,9>& a){
     return std::array<T,9>({a[0],a[3],a[6],a[1],a[4],a[7],a[2],a[5],a[8]});
   }
   
   class PrimitiveTransform{
   private:
     Bravais bravais;    
   public:
     PrimitiveTransform(const Bravais c): bravais{c} {}
     [[deprecated("Call with an enum Bravais instead")]] PrimitiveTransform(const Spacegroup& s): bravais{s.bravais} {}
     [[deprecated("Call with an enum Bravais instead")]] PrimitiveTransform(const int hall){
       Spacegroup s(hall);
       this->bravais = s.bravais;
     }
     std::array<double,9> get_P(void) const {
       switch (bravais){
         case Bravais::_: throw std::runtime_error("Invalid Bravais centring");
         case Bravais::I: return {-0.5, 0.5, 0.5,  0.5,-0.5, 0.5,  0.5, 0.5,-0.5};
         case Bravais::F: return {  0 , 0.5, 0.5,  0.5,  0 , 0.5,  0.5, 0.5,  0 };
         case Bravais::A: return {  1 ,  0 ,  0 ,   0 , 0.5,-0.5,   0 , 0.5, 0.5};
         case Bravais::B: return { 0.5,  0 ,-0.5,   0 ,  1 ,  0 ,  0.5,  0 , 0.5};
         case Bravais::C: return { 0.5, 0.5,  0 , -0.5, 0.5,  0 ,   0 ,  0 ,  1 };
         case Bravais::R: return {2./3.,-1./3.,-1./3.,  1./3., 1./3.,-2./3.,  1./3., 1./3., 1./3.};
         default: return {  1 ,  1 ,  1,    1 ,  1 ,  1 ,   1 ,  1 ,  1 };
       }
     }
     std::array<int,9> get_invP(void) const {
       switch (bravais){
         case Bravais::_: throw std::runtime_error("Invalid Bravais centring");
         case Bravais::I: return { 0, 1, 1,  1, 0, 1,  1, 1, 0};
         case Bravais::F: return {-1, 1, 1,  1,-1, 1,  1, 1,-1};
         case Bravais::A: return { 1, 0, 0,  0, 1, 1,  0,-1, 1};
         case Bravais::B: return { 1, 0, 1,  0, 1, 0, -1, 0, 1};
         case Bravais::C: return { 1,-1, 0,  1, 1, 0,  0, 0, 1};
         case Bravais::R: return { 1, 0, 1, -1, 1, 1,  0,-1, 1};
         default: return { 1, 0, 0,  0, 1, 0,  0, 0, 1};
       }
     }
     std::array<double,9> get_Pt(void) const { return transpose(this->get_P()); }
     std::array<int,9> get_invPt(void) const { return transpose(this->get_invP());}
     void print(){
       std::array<double,9> M = this->get_P();
       std::array<int,9> invM = this->get_invP();
       for (int i=0; i<3; ++i){
         printf("%3s", i==1 ? "to" :"");
         for (int j=0; j<3; ++j) printf(" % 4.2f",M[i*3+j]);
         printf("%5s", i==1 ? "from" : "");
         for (int j=0; j<3; ++j) printf(" % 2d",invM[i*3+j]);
         printf("\n");
       }
     }
     bool does_anything() const { return (bravais!=Bravais::P);}
     bool does_nothing() const { return (bravais==Bravais::P);}
     std::string string_repr() const {
       std::string repr = "<" + bravais_string(bravais) + " PrimitiveTransform object>";
       return repr;
     }
   };
   
   
   struct PrimitiveTraits{
     using P = double;
     using invP = int;
   };
   } // end namespace brille
   #endif