ceph/src/boost/libs/histogram/examples/guide_histogram_serialization.cpp

   1 // Copyright 2015-2018 Hans Dembinski
   2 //
   3 // Distributed under the Boost Software License, Version 1.0.
   4 // (See accompanying file LICENSE_1_0.txt
   5 // or copy at http://www.boost.org/LICENSE_1_0.txt)
   6
   7 //[ guide_histogram_serialization
   8
   9 #include <boost/archive/text_iarchive.hpp>
  10 #include <boost/archive/text_oarchive.hpp>
  11 #include <boost/histogram.hpp>
  12 #include <boost/histogram/serialization.hpp> // includes serialization code
  13 #include <cassert>
  14 #include <sstream>
  15
  16 int main() {
  17   using namespace boost::histogram;
  18
  19   auto a = make_histogram(axis::regular<>(3, -1.0, 1.0, "axis 0"),
  20                           axis::integer<>(0, 2, "axis 1"));
  21   a(0.5, 1);
  22
  23   std::string buf; // to hold persistent representation
  24
  25   // store histogram
  26   {
  27     std::ostringstream os;
  28     boost::archive::text_oarchive oa(os);
  29     oa << a;
  30     buf = os.str();
  31   }
  32
  33   auto b = decltype(a)(); // create a default-constructed second histogram
  34
  35   assert(b != a); // b is empty, a is not
  36
  37   // load histogram
  38   {
  39     std::istringstream is(buf);
  40     boost::archive::text_iarchive ia(is);
  41     ia >> b;
  42   }
  43
  44   assert(b == a); // now b is equal to a
  45 }
  46
  47 //]