[io] Add function to read and write container from and to file

dumux/io/CMakeLists.txt

@@ -3,6 +3,7 @@
 install(FILES
 adaptivegridrestart.hh
 artgridcreator.hh
+container.hh
 cpgridcreator.hh
 gnuplotinterface.hh
 gridcreator.hh

dumux/io/container.hh

+// -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+// vi: set et ts=4 sw=4 sts=4:
+/*****************************************************************************
+ *   See the file COPYING for full copying permissions.                      *
+ *                                                                           *
+ *   This program is free software: you can redistribute it and/or modify    *
+ *   it under the terms of the GNU General Public License as published by    *
+ *   the Free Software Foundation, either version 2 of the License, or       *
+ *   (at your option) any later version.                                     *
+ *                                                                           *
+ *   This program 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 General Public License for more details.                            *
+ *                                                                           *
+ *   You should have received a copy of the GNU General Public License       *
+ *   along with this program.  If not, see <http://www.gnu.org/licenses/>.   *
+ *****************************************************************************/
+/*!
+ * \file
+ * \brief Free functions to write and read a sequence container to and from a file
+ * \note Reading should work for all sequence containers providing begin, end, and push_back
+ *       (e.g. std::vector, std::deque, std::list), so not for e.g. std::array.
+ *       Writing only needs begin and end member functions returning iterators.
+ */
+#ifndef DUMUX_IO_CONTAINER_HH
+#define DUMUX_IO_CONTAINER_HH
+
+#include <iostream>
+#include <fstream>
+
+namespace Dumux {
+
+/*!
+ * \brief Writes a container to file
+ * \param v The container, requires being() and end() method
+ * \param filename The filename to write to
+ *
+ * \usage std::vector<double>(5, 0.0) v; writeContainerToFile(v, "myvector.txt");
+ */
+template<typename Container>
+void writeContainerToFile(const Container& v,
+                          const std::string& filename)
+{
+    std::ofstream outfile(filename, std::ios::out);
+    std::ostream_iterator<typename Container::value_type> it(outfile, "\n");
+    std::copy(v.begin(),v.end(), it);
+}
+
+/*!
+ * \brief Read a simple text file into a container
+ * \param filename The filename to write to
+ * \tparam Container  The container type, requires being(), end(), push_back() method
+ *
+ * \usage auto v = readFileToContainer<std::vector<double>>("myvector.txt");
+ */
+template<typename Container>
+Container readFileToContainer(const std::string& filename)
+{
+    Container v;
+    std::ifstream infile(filename, std::ios::in);
+    std::istream_iterator<typename Container::value_type> it(infile);
+    std::copy(it, std::istream_iterator<typename Container::value_type>(), std::back_inserter(v));
+    return v;
+}
+
+} // end namespace Dumux
+
+#endif

test/io/CMakeLists.txt

 add_subdirectory("gnuplotinterface")
-add_subdirectory("gridcreator")
\ No newline at end of file
+add_subdirectory("gridcreator")
+add_subdirectory("container")

test/io/container/CMakeLists.txt

+add_dumux_test(test_container_io test_container_io test_container_io.cc
+  ${CMAKE_CURRENT_BINARY_DIR}/test_container_io)
+
+#install sources
+install(FILES
+test_container_io.cc
+DESTINATION ${CMAKE_INSTALL_INCLUDEDIR}/dumux/test/io/container)

test/io/container/test_container_io.cc

+// -*- mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+// vi: set et ts=4 sw=4 sts=4:
+/*****************************************************************************
+ *   See the file COPYING for full copying permissions.                      *
+ *                                                                           *
+ *   This program is free software: you can redistribute it and/or modify    *
+ *   it under the terms of the GNU General Public License as published by    *
+ *   the Free Software Foundation, either version 2 of the License, or       *
+ *   (at your option) any later version.                                     *
+ *                                                                           *
+ *   This program 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 General Public License for more details.                            *
+ *                                                                           *
+ *   You should have received a copy of the GNU General Public License       *
+ *   along with this program.  If not, see <http://www.gnu.org/licenses/>.   *
+ *****************************************************************************/
+/*!
+ * \file
+ * \brief Test writing and reading sequence container to and from file
+ */
+#include <config.h>
+
+#include <algorithm>
+#include <vector>
+#include <list>
+#include <deque>
+#include <array>
+#include <initializer_list>
+
+#include <dune/common/float_cmp.hh>
+#include <dune/common/fvector.hh>
+#include <dune/istl/bvector.hh>
+
+#include <dumux/io/container.hh>
+
+namespace Dumux {
+
+template<typename T>
+bool testContainerIO(const T& c0)
+{
+    writeContainerToFile(c0, "container.txt");
+    auto c1 = readFileToContainer<T>("container.txt");
+    return std::equal(c0.begin(), c0.end(), c1.begin());
+}
+
+template<typename T>
+bool testContainerIO(const std::initializer_list<typename T::value_type>& init)
+{
+    T c0(init);
+    writeContainerToFile(c0, "container.txt");
+    auto c1 = readFileToContainer<T>("container.txt");
+    return std::equal(c0.begin(), c0.end(), c1.begin());
+}
+
+template<typename T>
+bool testContainerWriter(const T& c0)
+{
+    writeContainerToFile(c0, "container.txt");
+    auto c1 = readFileToContainer<std::vector<std::decay_t<decltype(*c0.begin())>>>("container.txt");
+    return std::equal(c0.begin(), c0.end(), c1.begin());
+}
+
+} // end namespace Dumux
+
+////////////////////////
+// the main function
+////////////////////////
+int main()
+{
+    bool passed = true;
+
+    // we can read and write into
+    // std::vector, std::list, std::deque
+    // we can even read and write containers of FieldVectors (very convenient!)
+    auto doublei = {5.3, 6.1, 7.2, 5.66, 2.89, 8.123};
+    passed = passed && Dumux::testContainerIO<std::vector<double>>(doublei);
+    passed = passed && Dumux::testContainerIO<std::list<double>>(doublei);
+    passed = passed && Dumux::testContainerIO<std::deque<double>>(doublei);
+    if (!passed) return 1;
+
+    auto inti = {5, 6, 7, 5, 2, 8};
+    passed = passed && Dumux::testContainerIO<std::vector<int>>(inti);
+    passed = passed && Dumux::testContainerIO<std::list<int>>(inti);
+    passed = passed && Dumux::testContainerIO<std::deque<int>>(inti);
+    if (!passed) return 1;
+
+    std::initializer_list<std::string> stringi = {"5", "6", "7", "5", "2", "8"};
+    passed = passed && Dumux::testContainerIO<std::vector<std::string>>(stringi);
+    passed = passed && Dumux::testContainerIO<std::list<std::string>>(stringi);
+    passed = passed && Dumux::testContainerIO<std::deque<std::string>>(stringi);
+    if (!passed) return 1;
+
+    auto fvector2i = {Dune::FieldVector<double, 2>(0.0), Dune::FieldVector<double, 2>(1.0), Dune::FieldVector<double, 2>(2.0)};
+    passed = passed && Dumux::testContainerIO<std::vector<Dune::FieldVector<double, 2>>>(fvector2i);
+    passed = passed && Dumux::testContainerIO<std::list<Dune::FieldVector<double, 2>>>(fvector2i);
+    passed = passed && Dumux::testContainerIO<std::deque<Dune::FieldVector<double, 2>>>(fvector2i);
+    if (!passed) return 1;
+
+    auto fvector3i = {Dune::FieldVector<double, 3>(0.0), Dune::FieldVector<double, 3>(1.0), Dune::FieldVector<double, 3>(2.0)};
+    passed = passed && Dumux::testContainerIO<std::vector<Dune::FieldVector<double, 3>>>(fvector3i);
+    passed = passed && Dumux::testContainerIO<std::list<Dune::FieldVector<double, 3>>>(fvector3i);
+    passed = passed && Dumux::testContainerIO<std::deque<Dune::FieldVector<double, 3>>>(fvector3i);
+    if (!passed) return 1;
+
+    // we can write also std::arrays (all container providing begin and end)
+    passed = passed && Dumux::testContainerWriter<std::array<double, 2>>(std::array<double, 2>{1.0, 2.0});
+    passed = passed && Dumux::testContainerWriter<std::array<int, 2>>(std::array<int, 2>{1, 2});
+    passed = passed && Dumux::testContainerWriter<std::array<std::string, 2>>(std::array<std::string, 2>{"1.0", "2.0"});
+    passed = passed && Dumux::testContainerWriter<std::array<Dune::FieldVector<double, 3>, 2>>(
+                        std::array<Dune::FieldVector<double, 3>, 2>{Dune::FieldVector<double, 3>(0.0), Dune::FieldVector<double, 3>(1.0)});
+    if (!passed) return 1;
+
+    return 0;
+}