From 3720103f41dd2e2f6a92d36007602c1bfe35ad84 Mon Sep 17 00:00:00 2001
From: Michael Marshall <michael.marshall@ed.ac.uk>
Date: Sat, 9 Feb 2019 17:12:36 +0000
Subject: [PATCH] Adding Eigen::Tensor still WIP

---
 Grid/serialisation/BaseIO.h          | 57 +++++++++++++++++++++++-----
 Grid/serialisation/VectorUtils.h     |  2 +-
 tests/hadrons/Test_hadrons_distil.cc |  8 +++-
 3 files changed, 55 insertions(+), 12 deletions(-)

diff --git a/Grid/serialisation/BaseIO.h b/Grid/serialisation/BaseIO.h
index e96a2f9a..26b6ab5a 100644
--- a/Grid/serialisation/BaseIO.h
+++ b/Grid/serialisation/BaseIO.h
@@ -55,14 +55,21 @@ namespace Grid {
     template <typename U>
     typename std::enable_if<!std::is_base_of<Serializable, U>::value, void>::type
     write(const std::string& s, const U &output);
+    template <typename Scalar_, int NumIndices_, int Options_, typename IndexType_>
+    typename std::enable_if<std::is_arithmetic<Scalar_>::value || Grid::is_complex<Scalar_>::value, void>::type
+    write(const std::string &s, const Eigen::Tensor<Scalar_, NumIndices_, Options_, IndexType_> &output);
+    template<typename U, int NumIndices_, int Options_, typename IndexType_>
+    void write(const std::string &s, const Eigen::Tensor<iScalar<U>, NumIndices_, Options_, IndexType_> &output);
+    template<typename U, int N, int NumIndices_, int Options_, typename IndexType_>
+    void write(const std::string &s, const Eigen::Tensor<iVector<U, N>, NumIndices_, Options_, IndexType_> &output);
+    template<typename U, int N, int NumIndices_, int Options_, typename IndexType_>
+    void write(const std::string &s, const Eigen::Tensor<iMatrix<U, N>, NumIndices_, Options_, IndexType_> &output);
     template <typename U>
     void write(const std::string &s, const iScalar<U> &output);
     template <typename U, int N>
     void write(const std::string &s, const iVector<U, N> &output);
     template <typename U, int N>
     void write(const std::string &s, const iMatrix<U, N> &output);
-    template <typename Scalar_, int NumIndices_>
-    void write(const std::string &s, const Eigen::Tensor<Scalar_, NumIndices_, Eigen::RowMajor> &output);
     
     void         scientificFormat(const bool set);
     bool         isScientific(void);
@@ -145,6 +152,44 @@ namespace Grid {
     upcast->writeDefault(s, output);
   }
 
+  // Eigen::Tensors of arithmetic/complex base type
+  template <typename T>
+  template <typename Scalar_, int NumIndices_, int Options_, typename IndexType_>
+  typename std::enable_if<std::is_arithmetic<Scalar_>::value || Grid::is_complex<Scalar_>::value, void>::type
+  Writer<T>::write(const std::string &s, const Eigen::Tensor<Scalar_, NumIndices_, Options_, IndexType_> &output)
+  {
+    //upcast->writeDefault(s, tensorToVec(output));
+    std::cout << "I really should add code to write Eigen::Tensor (arithmetic/complex) ..." << std::endl;
+  }
+
+  // Eigen::Tensors of iScalar<U>
+  template <typename T>
+  template<typename U, int NumIndices_, int Options_, typename IndexType_>
+  void Writer<T>::write(const std::string &s, const Eigen::Tensor<iScalar<U>, NumIndices_, Options_, IndexType_> &output)
+  {
+    //upcast->writeDefault(s, tensorToVec(output));
+    std::cout << "I really should add code to write Eigen::Tensor (iScalar) ..." << std::endl;
+  }
+
+  // Eigen::Tensors of iVector<U, N>
+  template <typename T>
+  template<typename U, int N, int NumIndices_, int Options_, typename IndexType_>
+  void Writer<T>::write(const std::string &s, const Eigen::Tensor<iVector<U, N>, NumIndices_, Options_, IndexType_> &output)
+  {
+    //upcast->writeDefault(s, tensorToVec(output));
+    std::cout << "I really should add code to write Eigen::Tensor (iVector) ..." << std::endl;
+  }
+
+  // Eigen::Tensors of iMatrix<U, N>
+  template <typename T>
+  template<typename U, int N, int NumIndices_, int Options_, typename IndexType_>
+  void Writer<T>::write(const std::string &s, const Eigen::Tensor<iMatrix<U, N>, NumIndices_, Options_, IndexType_> &output)
+  {
+    //upcast->writeDefault(s, tensorToVec(output));
+    std::cout << "I really should add code to write Eigen::Tensor (iMatrix) ..." << std::endl;
+  }
+
+
   template <typename T>
   template <typename U>
   void Writer<T>::write(const std::string &s, const iScalar<U> &output)
@@ -166,14 +211,6 @@ namespace Grid {
     upcast->writeDefault(s, tensorToVec(output));
   }
 
-  template <typename T>
-  template <typename Scalar_, int NumIndices_>
-  void Writer<T>::write(const std::string &s, const Eigen::Tensor<Scalar_, NumIndices_, Eigen::RowMajor> &output)
-  {
-    //upcast->writeDefault(s, tensorToVec(output));
-    std::cout << "I really should add code to write Eigen::Tensor ..." << std::endl;
-  }
-  
   template <typename T>
   void Writer<T>::scientificFormat(const bool set)
   {
diff --git a/Grid/serialisation/VectorUtils.h b/Grid/serialisation/VectorUtils.h
index b6b95c10..3372c8ad 100644
--- a/Grid/serialisation/VectorUtils.h
+++ b/Grid/serialisation/VectorUtils.h
@@ -436,4 +436,4 @@ std::string vecToStr(const std::vector<T> &v)
   return sstr.str();
 }
 
-#endif
\ No newline at end of file
+#endif
diff --git a/tests/hadrons/Test_hadrons_distil.cc b/tests/hadrons/Test_hadrons_distil.cc
index 1529eb15..6be63841 100644
--- a/tests/hadrons/Test_hadrons_distil.cc
+++ b/tests/hadrons/Test_hadrons_distil.cc
@@ -424,12 +424,15 @@ bool DebugEigenTest()
 }
 
 typedef iMatrix<Complex,7> OddBall;
+typedef Eigen::Tensor<int, 3, Eigen::RowMajor> TensorInt;
+typedef Eigen::Tensor<std::complex<double>, 3, Eigen::RowMajor> TensorComplex;
+typedef Eigen::Tensor<OddBall, 3, Eigen::RowMajor> TensorOddBall;
 
 // From Test_serialisation.cc
 class myclass: Serializable {
 public:
   GRID_SERIALIZABLE_CLASS_MEMBERS(myclass
-                                  , OddBall, critter
+                                  //, OddBall, critter
                                   , SpinColourVector, scv
                                   , SpinColourMatrix, scm
                                   );
@@ -465,6 +468,9 @@ bool DebugIOTest(void) {
   ioTest<Hdf5Writer, Hdf5Reader, SpinColourVector>("iotest_vector.h5", scv, "SpinColourVector");
   myclass o;
   ioTest<Hdf5Writer, Hdf5Reader, myclass>("iotest_object.h5", o, "myclass_object_instance_name");
+  TensorInt t(3,6,2);
+  ioTest<Hdf5Writer, Hdf5Reader, TensorInt>("iotest_tensor.h5", t, "eigen_tensor_instance_name");
+
   return true;
 }
 #endif