Tag the Gmsh example meshes bottom, left, top, right

Renumber the physical groups of rect_quad.msh and rhom_quad.msh so their
boundary keys match the structured mesh (0 bottom, 1 left, 2 top,
3 right), and swap the left/right boundary conditions in the two Gmsh
examples accordingly. The meshes themselves are unchanged.

Correct the tests/meshes README, which said the example mesh was
identical to rect_quad_quadratic.msh: the test meshes keep their
bottom, right, top, left tags.

Author: nikoscham

examples/heatConductionScript/heatConduction2DFin/heatConduction2DFinGmsh.js

@@ -47,9 +47,9 @@ async function main() {
 
   // Define boundary conditions
   model.addBoundaryCondition("0", ["constantTemperature", 200]); // Bottom boundary
-  model.addBoundaryCondition("1", ["constantTemperature", 200]); // Right boundary
+  model.addBoundaryCondition("1", ["symmetry"]); // Left boundary
   model.addBoundaryCondition("2", ["convection", 1, 20]); // Top boundary
-  model.addBoundaryCondition("3", ["symmetry"]); // Left boundary
+  model.addBoundaryCondition("3", ["constantTemperature", 200]); // Right boundary
 
   // Solve the problem
   const { solutionVector, nodesCoordinates } = model.solve();

examples/heatConductionScript/heatConduction2DFin/heatConduction2DRhomFinGmsh.js

@@ -47,9 +47,9 @@ async function main() {
 
   // Define boundary conditions
   model.addBoundaryCondition("0", ["constantTemperature", 200]); // Bottom boundary
-  model.addBoundaryCondition("1", ["constantTemperature", 200]); // Right boundary
+  model.addBoundaryCondition("1", ["symmetry"]); // Left boundary
   model.addBoundaryCondition("2", ["convection", 1, 20]); // Top boundary
-  model.addBoundaryCondition("3", ["symmetry"]); // Left boundary
+  model.addBoundaryCondition("3", ["constantTemperature", 200]); // Right boundary
 
   // Solve the problem
   model.setSolverMethod("lusolve");

examples/heatConductionScript/heatConduction2DFin/rect_quad.msh

@@ -4,9 +4,9 @@ $EndMeshFormat
 $PhysicalNames
 5
 1 1 "bottom"
-1 2 "right"
+1 2 "left"
 1 3 "top"
-1 4 "left"
+1 4 "right"
 2 5 "domain"
 $EndPhysicalNames
 $Entities
@@ -16,9 +16,9 @@ $Entities
 3 4 2 0 0 
 4 0 2 0 0 
 1 0 0 0 4 0 0 1 1 2 1 -2 
-2 4 0 0 4 2 0 1 2 2 2 -3 
+2 4 0 0 4 2 0 1 4 2 2 -3 
 3 0 2 0 4 2 0 1 3 2 3 -4 
-4 0 0 0 0 2 0 1 4 2 4 -1 
+4 0 0 0 0 2 0 1 2 2 4 -1 
 1 0 0 0 4 2 0 1 5 4 1 2 3 4 
 $EndEntities
 $Nodes

examples/heatConductionScript/heatConduction2DFin/rhom_quad.msh

@@ -4,9 +4,9 @@ $EndMeshFormat
 $PhysicalNames
 5
 1 1 "bottom"
-1 2 "right"
+1 2 "left"
 1 3 "top"
-1 4 "left"
+1 4 "right"
 2 5 "domain"
 $EndPhysicalNames
 $Entities
@@ -16,9 +16,9 @@ $Entities
 3 5 2 0 0 
 4 1 2 0 0 
 1 0 0 0 4 0 0 1 1 2 1 -2 
-2 4 0 0 5 2 0 1 2 2 2 -3 
+2 4 0 0 5 2 0 1 4 2 2 -3 
 3 1 2 0 5 2 0 1 3 2 3 -4 
-4 0 0 0 1 2 0 1 4 2 4 -1 
+4 0 0 0 1 2 0 1 2 2 4 -1 
 1 0 0 0 5 2 0 1 5 4 1 2 3 4 
 $EndEntities
 $Nodes

tests/meshes/README.md

@@ -48,8 +48,10 @@ Then run (Gmsh 4.12.1 was used):
 gmsh rect.geo -save -format msh41 -o <mesh file>
 ```
 
-`rect_quad_quadratic.msh` is identical to `rect_quad.msh` used by the
-[`heatConduction2DFinGmsh.js`](../../examples/heatConductionScript/heatConduction2DFin/heatConduction2DFinGmsh.js) example.
+`rect_quad_quadratic.msh` has the same nodes and elements as `rect_quad.msh` used by the
+[`heatConduction2DFinGmsh.js`](../../examples/heatConductionScript/heatConduction2DFin/heatConduction2DFinGmsh.js) example,
+but its physical groups are tagged bottom, right, top, left; the example mesh tags them bottom, left, top, right,
+like the sides of FEAScript structured meshes.
 
 ## Used by