From 3cfd9dff9db5d54252192bf49d48e2affe9adf53 Mon Sep 17 00:00:00 2001
From: Adam G Nelson <nelsonag@umich.edu>
Date: Mon, 10 Dec 2018 20:01:03 -0500
Subject: [PATCH] Added xtensor read_dataset

---
 include/openmc/hdf5_interface.h | 28 ++++++++++++++++++++++++++++
 src/urr.cpp                     | 21 ++++++---------------
 2 files changed, 34 insertions(+), 15 deletions(-)

diff --git a/include/openmc/hdf5_interface.h b/include/openmc/hdf5_interface.h
index 0c940342c..5b5d2a999 100644
--- a/include/openmc/hdf5_interface.h
+++ b/include/openmc/hdf5_interface.h
@@ -271,6 +271,34 @@ void read_dataset(hid_t obj_id, const char* name, xt::xarray<T>& arr, bool indep
   close_dataset(dset);
 }
 
+
+template <typename T, std::size_t N>
+void read_dataset(hid_t obj_id, const char* name, xt::xtensor<T, N>& arr, bool indep=false)
+{
+  // Open dataset and read array
+  hid_t dset = open_dataset(obj_id, name);
+
+  // Get shape of dataset
+  std::vector<hsize_t> hsize_t_shape = object_shape(dset);
+  close_dataset(dset);
+
+  // cast from hsize_t to size_t
+  std::vector<size_t> shape(hsize_t_shape.size());
+  for (int i = 0; i < shape.size(); i++) {
+    shape[i] = static_cast<size_t>(hsize_t_shape[i]);
+  }
+
+  // Allocate new xarray to read data into
+  xt::xarray<T> xarr(shape);
+
+  // Read data from the dataset
+  read_dataset(obj_id, name, xarr);
+
+  // Copy into xtensor
+  arr = xarr;
+
+}
+
 template <typename T, std::size_t N>
 void read_dataset_as_shape(hid_t obj_id, const char* name,
                            xt::xtensor<T, N>& arr, bool indep=false)
diff --git a/src/urr.cpp b/src/urr.cpp
index 4a6643bfc..28ad2505f 100644
--- a/src/urr.cpp
+++ b/src/urr.cpp
@@ -18,23 +18,14 @@ UrrData::UrrData(hid_t group_id)
   read_attribute(group_id, "multiply_smooth", temp_multiply_smooth);
   multiply_smooth_ = (temp_multiply_smooth == 1);
 
-  // read the enrgies at which tables exist
-  hid_t dset = open_dataset(group_id, "energy");
-  hsize_t dims[1];
-  get_shape(dset, dims);
-  close_dataset(dset);
-  n_energy_ = static_cast<int>(dims[0]);
-  energy_ = xt::xtensor<double, 1>({dims[0]}, 0.);
-  read_dataset_as_shape(group_id, "energy", energy_);
+  // read the energies at which tables exist
+  read_dataset(group_id, "energy", energy_);
+
+  // Set n_energy_
+  n_energy_ = energy_.shape()[0];
 
   // Read URR tables
-  dset = open_dataset(group_id, "table");
-  hsize_t dims3[3];
-  get_shape(dset, dims3);
-  close_dataset(dset);
-  xt::xarray<double> temp_arr({dims3[0], dims3[1], dims3[2]}, 0.);
-  read_dataset(group_id, "table", temp_arr);
-  prob_ = temp_arr;
+  read_dataset(group_id, "table", prob_);
 }
 
 }
\ No newline at end of file