From 0eba4e39ccfc6dd99f9bb939c38bbad226a88c06 Mon Sep 17 00:00:00 2001
From: Martin Diehl <mail@martin-diehl.net>
Date: Sun, 26 Jan 2020 14:18:16 +0100
Subject: [PATCH] trying to make the whole procedure understandable

---
 src/element.f90 | 113 ++++++++++++++++++++++++------------------------
 1 file changed, 57 insertions(+), 56 deletions(-)

diff --git a/src/element.f90 b/src/element.f90
index 1159d401a..6ce23a9da 100644
--- a/src/element.f90
+++ b/src/element.f90
@@ -43,38 +43,39 @@ module element
  
   integer, dimension(NELEMTYPE), parameter :: NNODE = &
     [ &
-        3, & ! 2D 3node 1ip
-        6, & ! 2D 6node 3ip
-        4, & ! 2D 4node 4ip
-        8, & ! 2D 8node 9ip
-        8, & ! 2D 8node 4ip
-        !--------------------
-        4, & ! 3D 4node 1ip
-        5, & ! 3D 5node 4ip
-       10, & ! 3D 10node 4ip
-        6, & ! 3D 6node 6ip
-        8, & ! 3D 8node 1ip
-        8, & ! 3D 8node 8ip
-       20, & ! 3D 20node 8ip
-       20  & ! 3D 20node 27ip
+        3, & ! 2D, 1 IP
+        6, & ! 2D, 3 IP
+        4, & ! 2D, 4 IP
+        8, & ! 2D, 9 IP
+        8, & ! 2D, 4 IP
+        !----------------------
+        4, & ! 3D, 1 IP
+        5, & ! 3D, 4 IP
+       10, & ! 3D, 4 IP
+        6, & ! 3D, 6 IP
+        8, & ! 3D, 1 IP
+        8, & ! 3D, 8 IP
+       20, & ! 3D, 8 IP
+       20  & ! 3D, 27 IP
     ]                                                                                               !< number of nodes that constitute a specific type of element
  
   integer, dimension(NELEMTYPE), parameter :: GEOMTYPE = &
     [ &
-        1, & 
-        2, & 
-        3, & 
-        4, & 
-        3, & 
-        5, & 
-        6, & 
-        6, & 
-        7, & 
-        8, & 
-        9, & 
-        9, & 
-       10  & 
-    ]                                                                                               !< geometry type of particular element type
+        1, & ! 1 triangle
+        2, & ! 3 quadrilaterals
+        3, & ! 4 quadrilaterals
+        4, & ! 9 quadrilaterals
+        3, & ! 4 quadrilaterals
+        !----------------------
+        5, & ! 1 tetrahedron
+        6, & ! 4 hexahedrons
+        6, & ! 4 hexahedrons
+        7, & ! 6 hexahedrons
+        8, & ! 1 hexahedron
+        9, & ! 8 hexahedrons
+        9, & ! 8 hexahedrons
+       10  & ! 27 hexahedrons
+    ]                                                                                               !< geometry type (same number of cell nodes and IPs)
  
   integer, dimension(maxval(GEOMTYPE)), parameter :: NCELLNODE = &
     [ &
@@ -88,7 +89,7 @@ module element
         8, &
        27, &
        64  &
-    ]                                                                                               !< number of cell nodes in a specific geometry type
+    ]                                                                                               !< number of cell nodes
  
   integer, dimension(maxval(GEOMTYPE)), parameter :: NIP = &
     [ &
@@ -102,45 +103,45 @@ module element
         1, & 
         8, & 
        27  & 
-    ]                                                                                               !< number of IPs in a specific geometry type
+    ]                                                                                               !< number of IPs
  
   integer, dimension(maxval(GEOMTYPE)), parameter :: CELLTYPE = &
     [ &
-       1, & ! 2D 3node
-       2, & ! 2D 4node
-       2, & ! 2D 4node
-       2, & ! 2D 4node
-       3, & ! 3D 4node
-       4, & ! 3D 8node
-       4, & ! 3D 8node
-       4, & ! 3D 8node
-       4, & ! 3D 8node
-       4  & ! 3D 8node
-    ]                                                                                               !< cell type that is used by each geometry type
+       1, & ! 2D, 3 node (Triangle)
+       2, & ! 2D, 4 node (Quadrilateral)
+       2, & !   - " -
+       2, & !   - " -
+       3, & ! 3D, 4 node (Tetrahedron)
+       4, & ! 3D, 4 node (Hexahedron)
+       4, & !   - " -
+       4, & !   - " -
+       4, & !   - " -
+       4  & !   - " -
+    ]                                                                                               !< cell type
 
   integer, dimension(maxval(CELLTYPE)), parameter :: NIPNEIGHBOR = &
     [ &
-       3, & ! 2D 3node
-       4, & ! 2D 4node
-       4, & ! 3D 4node
-       6  & ! 3D 8node
-    ]                                                                                               !< number of ip neighbors / cell faces in a specific cell type 
+       3, &
+       4, &
+       4, &
+       6  &
+    ]                                                                                               !< number of ip neighbors / cell faces
 
   integer, dimension(maxval(CELLTYPE)), parameter :: NCELLNODEPERCELLFACE = &
     [ &
-       2, & ! 2D 3node
-       2, & ! 2D 4node
-       3, & ! 3D 4node
-       4  & ! 3D 8node
-    ]                                                                                               !< number of cell nodes in a specific cell type 
+       2, &
+       2, &
+       3, &
+       4  &
+    ]                                                                                               !< number of cell nodes per face
 
   integer, dimension(maxval(CELLTYPE)), parameter  :: NCELLNODEPERCELL = &
     [ &
-       3, & ! 2D 3node
-       4, & ! 2D 4node
-       4, & ! 3D 4node
-       8  & ! 3D 8node
-    ]                                                                                               !< number of cell nodes in a specific cell type
+       3, &
+       4, &
+       4, &
+       8  &
+    ]                                                                                               !< number of total cell nodes
 
   ! *** IPneighbor ***
   ! list of the neighborhood of each IP.