Повысить сериализацию матриц броненосцев

Question

Я пытаюсь убедиться, что сериализация работает для матриц, т. Е. Armadillo, и я получаю некоторые ошибки.

Я сделал простой пример случайной матрицы и пытаюсь сохранить содержимое с помощью boost в двоичном файле, а затем загрузить его с помощью boost:

#include <iostream>
#include <fstream>
#include <boost/archive/tmpdir.hpp>
#include <boost/archive/binary_oarchive.hpp>
#include <boost/archive/binary_iarchive.hpp>
#include <armadillo>


int main() {

arma::mat A = arma::randu<arma::mat>(4,5);


std::ofstream outputStream;
outputStream.open("bin.dat");
std::ostringstream oss;
boost::archive::binary_oarchive oa(outputStream);
oa & A;
outputStream.close(); getting error

arma::mat B;
std::ifstream inputStream;
inputStream.open("bin.dat", std::ifstream::in);
boost::archive::binary_iarchive ia(inputStream);
ia & B;
return 0;


}

Я получаю следующее ошибки (при выполнении команды: g++ -std=c++11 arma_boost.cpp -larmadillo -lboost_serialization):

In file included from /usr/include/boost/serialization/split_member.hpp:23:0,
                 from /usr/include/boost/serialization/nvp.hpp:33,
                 from /usr/include/boost/serialization/array.hpp:19,
                 from /usr/include/boost/archive/basic_binary_oprimitive.hpp:50,
                 from /usr/include/boost/archive/binary_oarchive_impl.hpp:22,
                 from /usr/include/boost/archive/binary_oarchive.hpp:21,
                 from arma_boost.cpp:4:
/usr/include/boost/serialization/access.hpp: In instantiation of ‘static void boost::serialization::access::serialize(Archive&, T&, unsigned int) [with Archive = boost::archive::binary_oarchive; T = arma::Mat<double>]’:
/usr/include/boost/serialization/serialization.hpp:69:69:   required from ‘void boost::serialization::serialize(Archive&, T&, unsigned int) [with Archive = boost::archive::binary_oarchive; T = arma::Mat<double>]’
/usr/include/boost/serialization/serialization.hpp:128:27:   required from ‘void boost::serialization::serialize_adl(Archive&, T&, unsigned int) [with Archive = boost::archive::binary_oarchive; T = arma::Mat<double>]’
/usr/include/boost/archive/detail/oserializer.hpp:152:5:   required from ‘void boost::archive::detail::oserializer<Archive, T>::save_object_data(boost::archive::detail::basic_oarchive&, const void*) const [with Archive = boost::archive::binary_oarchive; T = arma::Mat<double>]’
/usr/include/boost/archive/detail/oserializer.hpp:101:1:   required from ‘class boost::archive::detail::oserializer<boost::archive::binary_oarchive, arma::Mat<double> >’
/usr/include/boost/archive/detail/oserializer.hpp:253:13:   required from ‘static void boost::archive::detail::save_non_pointer_type<Archive>::save_standard::invoke(Archive&, const T&) [with T = arma::Mat<double>; Archive = boost::archive::binary_oarchive]’
/usr/include/boost/archive/detail/oserializer.hpp:308:28:   [ skipping 2 instantiation contexts, use -ftemplate-backtrace-limit=0 to disable ]
/usr/include/boost/archive/detail/common_oarchive.hpp:69:40:   required from ‘void boost::archive::detail::common_oarchive<Archive>::save_override(T&, int) [with T = const arma::Mat<double>; Archive = boost::archive::binary_oarchive]’
/usr/include/boost/archive/basic_binary_oarchive.hpp:75:7:   required from ‘void boost::archive::basic_binary_oarchive<Archive>::save_override(const T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_oarchive]’
/usr/include/boost/archive/binary_oarchive_impl.hpp:51:9:   required from ‘void boost::archive::binary_oarchive_impl<Archive, Elem, Tr>::save_override(T&, int) [with T = const arma::Mat<double>; Archive = boost::archive::binary_oarchive; Elem = char; Tr = std::char_traits<char>]’
/usr/include/boost/archive/detail/interface_oarchive.hpp:63:9:   required from ‘Archive& boost::archive::detail::interface_oarchive<Archive>::operator<<(T&) [with T = const arma::Mat<double>; Archive = boost::archive::binary_oarchive]’
/usr/include/boost/archive/detail/interface_oarchive.hpp:71:35:   required from ‘Archive& boost::archive::detail::interface_oarchive<Archive>::operator&(T&) [with T = arma::Mat<double>; Archive = boost::archive::binary_oarchive]’
arma_boost.cpp:19:6:   required from here
/usr/include/boost/serialization/access.hpp:118:9: error: ‘class arma::Mat<double>’ has no member named ‘serialize’
         t.serialize(ar, file_version);
         ^
/usr/include/boost/serialization/access.hpp: In instantiation of ‘static void boost::serialization::access::serialize(Archive&, T&, unsigned int) [with Archive = boost::archive::binary_iarchive; T = arma::Mat<double>]’:
/usr/include/boost/serialization/serialization.hpp:69:69:   required from ‘void boost::serialization::serialize(Archive&, T&, unsigned int) [with Archive = boost::archive::binary_iarchive; T = arma::Mat<double>]’
/usr/include/boost/serialization/serialization.hpp:128:27:   required from ‘void boost::serialization::serialize_adl(Archive&, T&, unsigned int) [with Archive = boost::archive::binary_iarchive; T = arma::Mat<double>]’
/usr/include/boost/archive/detail/iserializer.hpp:192:5:   required from ‘void boost::archive::detail::iserializer<Archive, T>::load_object_data(boost::archive::detail::basic_iarchive&, void*, unsigned int) const [with Archive = boost::archive::binary_iarchive; T = arma::Mat<double>]’
/usr/include/boost/archive/detail/iserializer.hpp:120:1:   required from ‘class boost::archive::detail::iserializer<boost::archive::binary_iarchive, arma::Mat<double> >’
/usr/include/boost/archive/detail/iserializer.hpp:387:13:   required from ‘static void boost::archive::detail::load_non_pointer_type<Archive>::load_standard::invoke(Archive&, const T&) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/detail/iserializer.hpp:439:28:   [ skipping 2 instantiation contexts, use -ftemplate-backtrace-limit=0 to disable ]
/usr/include/boost/archive/detail/common_iarchive.hpp:66:40:   required from ‘void boost::archive::detail::common_iarchive<Archive>::load_override(T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/basic_binary_iarchive.hpp:70:7:   required from ‘void boost::archive::basic_binary_iarchive<Archive>::load_override(T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/binary_iarchive_impl.hpp:50:9:   required from ‘void boost::archive::binary_iarchive_impl<Archive, Elem, Tr>::load_override(T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive; Elem = char; Tr = std::char_traits<char>]’
/usr/include/boost/archive/detail/interface_iarchive.hpp:60:9:   required from ‘Archive& boost::archive::detail::interface_iarchive<Archive>::operator>>(T&) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/detail/interface_iarchive.hpp:67:32:   required from ‘Archive& boost::archive::detail::interface_iarchive<Archive>::operator&(T&) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
arma_boost.cpp:26:6:   required from here
/usr/include/boost/serialization/access.hpp:118:9: error: ‘class arma::Mat<double>’ has no member named ‘serialize’

РЕДАКТИРОВАТЬ:

    #include <iostream>
    #include <fstream>
    #include <boost/archive/tmpdir.hpp>
    #include <boost/archive/binary_oarchive.hpp>
    #include <boost/archive/binary_iarchive.hpp>
    #include <armadillo>

    namespace boost {
    namespace serialization {

    template<class Archive>
    void serialize(Archive & ar, arma::mat &m, const unsigned int version)
    {

        ar & m.n_cols;          
        ar & m.n_rows;          
        ar & m.n_elem;                      


    }

      }
      }


    int main() {


  arma::mat A = arma::randu<arma::mat>(4,5);

  std::ofstream outputStream;
  outputStream.open("bin.dat");
  std::ostringstream oss;
  boost::archive::binary_oarchive oa(outputStream);
  oa & A;
  outputStream.close();

  arma::mat b; //tried also arma::mat b(4,5);
  std::ifstream inputStream;
  inputStream.open("bin.dat", std::ifstream::in);
  boost::archive::binary_iarchive ia(inputStream);
  ia & b;


      return 0;
    }

Это ошибки, которые я получаю:

In file included from /usr/include/boost/archive/basic_text_oprimitive.hpp:34:0,
                 from /usr/include/boost/archive/text_oarchive.hpp:30,
                 from arma_boost.cpp:3:
/usr/include/boost/archive/detail/check.hpp: In instantiation of ‘void boost::archive::detail::check_const_loading() [with T = const unsigned int]’:
/usr/include/boost/archive/detail/iserializer.hpp:577:38:   required from ‘void boost::archive::load(Archive&, T&) [with Archive = boost::archive::binary_iarchive; T = const unsigned int]’
/usr/include/boost/archive/detail/common_iarchive.hpp:66:40:   required from ‘void boost::archive::detail::common_iarchive<Archive>::load_override(T&, int) [with T = const unsigned int; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/basic_binary_iarchive.hpp:70:7:   required from ‘void boost::archive::basic_binary_iarchive<Archive>::load_override(T&, int) [with T = const unsigned int; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/binary_iarchive_impl.hpp:50:9:   required from ‘void boost::archive::binary_iarchive_impl<Archive, Elem, Tr>::load_override(T&, int) [with T = const unsigned int; Archive = boost::archive::binary_iarchive; Elem = char; Tr = std::char_traits<char>]’
/usr/include/boost/archive/detail/interface_iarchive.hpp:60:9:   required from ‘Archive& boost::archive::detail::interface_iarchive<Archive>::operator>>(T&) [with T = const unsigned int; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/detail/interface_iarchive.hpp:67:32:   [ skipping 8 instantiation contexts, use -ftemplate-backtrace-limit=0 to disable ]
/usr/include/boost/archive/detail/common_iarchive.hpp:66:40:   required from ‘void boost::archive::detail::common_iarchive<Archive>::load_override(T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/basic_binary_iarchive.hpp:70:7:   required from ‘void boost::archive::basic_binary_iarchive<Archive>::load_override(T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/binary_iarchive_impl.hpp:50:9:   required from ‘void boost::archive::binary_iarchive_impl<Archive, Elem, Tr>::load_override(T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive; Elem = char; Tr = std::char_traits<char>]’
/usr/include/boost/archive/detail/interface_iarchive.hpp:60:9:   required from ‘Archive& boost::archive::detail::interface_iarchive<Archive>::operator>>(T&) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/detail/interface_iarchive.hpp:67:32:   required from ‘Archive& boost::archive::detail::interface_iarchive<Archive>::operator&(T&) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
arma_boost.cpp:54:8:   required from here
/usr/include/boost/archive/detail/check.hpp:162:5: error: static assertion failed: typex::value
     BOOST_STATIC_ASSERT(typex::value);
     ^
In file included from /usr/include/boost/archive/binary_iarchive_impl.hpp:21:0,
                 from /usr/include/boost/archive/binary_iarchive.hpp:20,
                 from arma_boost.cpp:11:
/usr/include/boost/archive/basic_binary_iprimitive.hpp: In instantiation of ‘void boost::archive::basic_binary_iprimitive<Archive, Elem, Tr>::load(T&) [with T = const unsigned int; Archive = boost::archive::binary_iarchive; Elem = char; Tr = std::char_traits<char>]’:
/usr/include/boost/archive/detail/iserializer.hpp:107:9:   required from ‘static void boost::archive::load_access::load_primitive(Archive&, T&) [with Archive = boost::archive::binary_iarchive; T = const unsigned int]’
/usr/include/boost/archive/detail/iserializer.hpp:362:46:   required from ‘static void boost::archive::detail::load_non_pointer_type<Archive>::load_primitive::invoke(Archive&, T&) [with T = const unsigned int; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/detail/iserializer.hpp:439:28:   required from ‘static void boost::archive::detail::load_non_pointer_type<Archive>::invoke(Archive&, T&) [with T = const unsigned int; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/detail/iserializer.hpp:592:24:   required from ‘void boost::archive::load(Archive&, T&) [with Archive = boost::archive::binary_iarchive; T = const unsigned int]’
/usr/include/boost/archive/detail/common_iarchive.hpp:66:40:   required from ‘void boost::archive::detail::common_iarchive<Archive>::load_override(T&, int) [with T = const unsigned int; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/basic_binary_iarchive.hpp:70:7:   [ skipping 11 instantiation contexts, use -ftemplate-backtrace-limit=0 to disable ]
/usr/include/boost/archive/detail/common_iarchive.hpp:66:40:   required from ‘void boost::archive::detail::common_iarchive<Archive>::load_override(T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/basic_binary_iarchive.hpp:70:7:   required from ‘void boost::archive::basic_binary_iarchive<Archive>::load_override(T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/binary_iarchive_impl.hpp:50:9:   required from ‘void boost::archive::binary_iarchive_impl<Archive, Elem, Tr>::load_override(T&, int) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive; Elem = char; Tr = std::char_traits<char>]’
/usr/include/boost/archive/detail/interface_iarchive.hpp:60:9:   required from ‘Archive& boost::archive::detail::interface_iarchive<Archive>::operator>>(T&) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
/usr/include/boost/archive/detail/interface_iarchive.hpp:67:32:   required from ‘Archive& boost::archive::detail::interface_iarchive<Archive>::operator&(T&) [with T = arma::Mat<double>; Archive = boost::archive::binary_iarchive]’
arma_boost.cpp:54:8:   required from here
/usr/include/boost/archive/basic_binary_iprimitive.hpp:88:35: error: invalid conversion from ‘const void*’ to ‘void*’ [-fpermissive]
         load_binary(& t, sizeof(T));
                                   ^
/usr/include/boost/archive/basic_binary_iprimitive.hpp:149:1: note: initializing argument 1 of ‘void boost::archive::basic_binary_iprimitive<Archive, Elem, Tr>::load_binary(void*, std::size_t) [with Archive = boost::archive::binary_iarchive; Elem = char; Tr = std::char_traits<char>; std::size_t = long unsigned int]’
 basic_binary_iprimitive<Archive, Elem, Tr>::load_binary(
 ^

Answer 1

Armadillo предоставляет способ сохранить его тип в файл HDF5, который работает хорошо и может быть достаточно для вас.

Armadillo не поддерживает ускорение сериализации. Из руководства по сериализации boost мы видим, что класс должен иметь метод serialize, чтобы сериализовать его с boost. У броненосца такого метода нет, и это ошибка, которую вы получаете.

Кроме того, boost также позволяет ненавязчивому способу заставить класс работать с ним, что включает реализацию бесплатной функции serialize. Поскольку все, что вам нужно, это элементы в матрице и ее размерность, которые должны быть легко реализованы в соответствии с руководством по ускорению по сериализации .

---

Правка после редактирования вопроса.

Ошибка, которую вы получаете, действительно трудно сначала определить причину, но если вы прокомментируете строку с загрузочной частью (последняя строка перед возвратом), вы увидите, что она компилируется просто отлично. Если вы запустили исполняемый файл, то будет создан двоичный файл, и, таким образом, часть сериализации работает (но помните, что функция сериализации в вашем вопросе еще не сериализует элементы).

Теперь давайте go вернемся к ошибке

/usr/include/boost/archive/basic_binary_iprimitive.hpp:88:35: error: invalid conversion from ‘const void*’ to ‘void*’ [-fpermissive]
         load_binary(& t, sizeof(T));

Существует некоторый тип const (стирается с помощью boost и, следовательно, вы получаете void *), который не должен быть const. Если мы еще раз посмотрим на функцию serialize template и на учебник, мы увидим, что она используется как для сериализации, так и для загрузки, хотя в каждом случае тип Archive отличается. Это означает, что в коде ниже

ar & m.n_cols;          
ar & m.n_rows;          
ar & m.n_elem;  

во время сериализации значения считываются из m (ОК). Однако во время загрузки значения записываются в m, что не в порядке, так как это постоянные атрибуты. Это проблема. Чтобы это исправить, вам нужно разделить сохранение и загрузку на отдельные функции. Затем в реализации load вы можете использовать один из конструкторов броненосца, чтобы создать новую матрицу из загруженных данных. Самый простой способ сделать это - удалить шаблон и создать две перегрузки для функции сериализации

// This is the saving part
void serialize(boost::archive::binary_oarchive &ar, arma::mat &m,
               const unsigned int version) {

  ar &m.n_cols;
  ar &m.n_rows;
  ar &m.n_elem; // You don't really need this one

  // Note: You must also serialize the elements, which is currently missing
}

// This is the loading part
void serialize(boost::archive::binary_iarchive &ar, arma::mat &m,
               const unsigned int version) {

    // use one of the suitable constructors here
    m = arma::mat( ... )
}

Возможная полная реализация обеих перегрузок сериализации показана ниже (я проверил их, напечатав обе A и B матрицы и они одинаковые). Важно помнить, что вы должны прочитать значения в том же порядке, в котором вы их сохранили.

void serialize(boost::archive::binary_oarchive &ar, arma::mat &m,
               const unsigned int version) {
  // Since this is used only for reading I prefer the "<<" symbol instead of
  // "&", but "&" would work just fine
  ar << m.n_cols;
  ar << m.n_rows;
  // Loop to save each element in order
  for (unsigned i = 0; i < m.n_elem; i++) {
    // memptr gives us a pointer to the raw memory used to store the elements
    ar << m.memptr()[i];
  }
}

void serialize(boost::archive::binary_iarchive &ar, arma::mat &m,
               const unsigned int version) {

  arma::uword n_cols;
  arma::uword n_rows;
  ar >> n_cols;
  ar >> n_rows;
  m = arma::mat(n_rows, n_cols);

  // Loop to read each element in order
  for (unsigned i = 0; i < m.n_elem; i++) {
    ar >> m.memptr()[i];
  }
}

Отказ от ответственности: я на самом деле никогда раньше не использовал повышение сериализации, и, таким образом, возможно, есть лучший способ сделать это это.