From c5c12285b5ee21f9fedf4b34e567129259dea637 Mon Sep 17 00:00:00 2001
From: IgorBaratta <igorbaratta@gmail.com>
Date: Wed, 1 Nov 2023 12:42:27 +0000
Subject: [PATCH 1/2] remove print statements

---
 cpp/dolfinx/io/xdmf_function.cpp | 30 ++++++++++++++++--------------
 1 file changed, 16 insertions(+), 14 deletions(-)

diff --git a/cpp/dolfinx/io/xdmf_function.cpp b/cpp/dolfinx/io/xdmf_function.cpp
index 37a0ac3585b..bb65a2cc43f 100644
--- a/cpp/dolfinx/io/xdmf_function.cpp
+++ b/cpp/dolfinx/io/xdmf_function.cpp
@@ -24,21 +24,20 @@ using namespace dolfinx::io;
 
 namespace
 {
-/// Convert a value_rank to the XDMF string description (Scalar, Vector,
+/// Convert a shape to the XDMF string description (Scalar, Vector,
 /// Tensor).
-std::string rank_to_string(int value_rank)
+std::string shape_to_string(std::span<const std::size_t> shape)
 {
-  switch (value_rank)
-  {
-  case 0:
+  if (shape.size() == 0)
+    return "Scalar";
+  else if (shape.size() == 1 and shape[0] == 1)
     return "Scalar";
-  case 1:
+  else if (shape.size() == 1)
     return "Vector";
-  case 2:
+  else if (shape.size() == 2)
     return "Tensor";
-  default:
-    throw std::runtime_error("Range Error");
-  }
+  else
+    throw std::runtime_error("Unsupported value shape");
 }
 } // namespace
 
@@ -53,7 +52,8 @@ void xdmf_function::add_function(MPI_Comm comm, const fem::Function<T, U>& u,
   assert(u.function_space());
   auto mesh = u.function_space()->mesh();
   assert(mesh);
-  auto element = u.function_space()->element();
+  std::shared_ptr<const fem::FiniteElement<U>> element
+      = u.function_space()->element();
   assert(element);
 
   // FIXME: is the below check adequate for detecting a Lagrange
@@ -75,8 +75,9 @@ void xdmf_function::add_function(MPI_Comm comm, const fem::Function<T, U>& u,
   assert(dofmap);
   const int bs = dofmap->bs();
 
-  int rank = element->value_shape().size();
-  int num_components = std::pow(3, rank);
+  std::span<const std::size_t> value_shape = element->value_shape();
+  int num_components = std::reduce(value_shape.begin(), value_shape.end(), 1,
+                                   std::multiplies{});
 
   // Get fem::Function data values and shape
   std::vector<T> data_values;
@@ -174,7 +175,8 @@ void xdmf_function::add_function(MPI_Comm comm, const fem::Function<T, U>& u,
     pugi::xml_node attr_node = xml_node.append_child("Attribute");
     assert(attr_node);
     attr_node.append_attribute("Name") = attr_name.c_str();
-    attr_node.append_attribute("AttributeType") = rank_to_string(rank).c_str();
+    attr_node.append_attribute("AttributeType")
+        = shape_to_string(value_shape).c_str();
     attr_node.append_attribute("Center") = cell_centred ? "Cell" : "Node";
 
     std::span<const scalar_value_type_t<T>> u;

From 422bfa6f845763dc51372d8be073a4900967c098 Mon Sep 17 00:00:00 2001
From: Igor Baratta <igorbaratta@gmail.com>
Date: Thu, 2 Nov 2023 11:40:17 +0000
Subject: [PATCH 2/2] Update cpp/dolfinx/io/xdmf_function.cpp

Co-authored-by: Garth N. Wells <gnw20@cam.ac.uk>
---
 cpp/dolfinx/io/xdmf_function.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cpp/dolfinx/io/xdmf_function.cpp b/cpp/dolfinx/io/xdmf_function.cpp
index bb65a2cc43f..b3f9a6b5cfc 100644
--- a/cpp/dolfinx/io/xdmf_function.cpp
+++ b/cpp/dolfinx/io/xdmf_function.cpp
@@ -28,7 +28,7 @@ namespace
 /// Tensor).
 std::string shape_to_string(std::span<const std::size_t> shape)
 {
-  if (shape.size() == 0)
+  if (shape.empty())
     return "Scalar";
   else if (shape.size() == 1 and shape[0] == 1)
     return "Scalar";