Introduced a regression check to see if routine to map equispaced points to...

Introduced a regression check to see if routine to map equispaced points to coefficients works correctly.

CHANGELOG.md

@@ -36,7 +36,9 @@ v4.3.0
 - Add module to enable mean mode of 3DH1D to be extracted (!530)
 - Fix bug in C^0 projection (!541))
 - Add command line option to set number of homogeneous planes (!540)
-
+- Add module to project set of points to a fld file
+- Add support for interpolating to a box of points and fix ability to run interppointstofld module in parallel when using a plane or box option 
+	
 **MeshConvert:**
 - Enable face curvature inside core MeshConvert objects (!511)
 - Add linearise processing module to remove all curvature from high order

library/Demos/StdRegions/CMakeLists.txt

@@ -20,6 +20,10 @@ SET(StdProject_Diff2DSource  StdProject_Diff2D.cpp)
 ADD_NEKTAR_EXECUTABLE(StdProject_Diff2D demos StdProject_Diff2DSource)
 TARGET_LINK_LIBRARIES(StdProject_Diff2D ${LinkLibraries})
 
+SET(StdEquiToCoeff2DSource  StdEquiToCoeff2D.cpp)
+ADD_NEKTAR_EXECUTABLE(StdEquiToCoeff2D demos StdEquiToCoeff2DSource)
+TARGET_LINK_LIBRARIES(StdEquiToCoeff2D ${LinkLibraries})
+
 SET(StdProject3DSource  StdProject3D.cpp)
 ADD_NEKTAR_EXECUTABLE(StdProject3D demos StdProject3DSource)
 TARGET_LINK_LIBRARIES(StdProject3D ${LinkLibraries})

library/Demos/StdRegions/StdEquiToCoeff2D.cpp

+#include <cstdio>
+#include <cstdlib>
+#include <StdRegions/StdExpansion.h>
+#include <StdRegions/StdQuadExp.h>
+#include <StdRegions/StdTriExp.h>
+
+#include <StdRegions/StdRegions.hpp>
+
+using namespace Nektar;
+using namespace StdRegions; 
+using namespace std;
+
+NekDouble Tri_sol(NekDouble x, NekDouble y, int order1, int order2);
+
+int main(int argc, char *argv[])
+{
+  int           i,j;
+  int           order, nq1,nq2;
+  LibUtilities::PointsType    Qtype1,Qtype2;
+  LibUtilities::BasisType     btype1,btype2;
+  StdExpansion   *E;
+  
+  if(argc != 4)
+  {
+    fprintf(stderr,"Usage: EquiToCoeff2D   order  nq1 nq2  \n");
+    exit(1);
+  }
+  
+  btype1 = (LibUtilities::BasisType)  LibUtilities::eModified_A;
+  btype2 = (LibUtilities::BasisType)  LibUtilities::eModified_B;
+  
+  order  =  atoi(argv[1]);
+  nq1    =  atoi(argv[2]);
+  nq2    =  atoi(argv[3]);
+
+  Qtype1 = LibUtilities::eGaussLobattoLegendre; 
+  Qtype2 = LibUtilities::eGaussRadauMAlpha1Beta0;
+  
+  //-----------------------------------------------
+  // Define a segment expansion based on basis definition
+  const LibUtilities::PointsKey Pkey1(nq1,Qtype1);
+  const LibUtilities::PointsKey Pkey2(nq2,Qtype2);
+  const LibUtilities::BasisKey b1(btype1,order,Pkey1);
+  const LibUtilities::BasisKey b2(btype2,order,Pkey2);
+  E = new StdTriExp (b1,b2);
+  
+
+  Array<OneD,NekDouble> x = Array<OneD,NekDouble>(nq1*nq2);
+  Array<OneD,NekDouble> y = Array<OneD,NekDouble>(nq1*nq2);
+  E->GetCoords(x,y);
+
+
+  Array<OneD,NekDouble> sol = Array<OneD,NekDouble>(nq1*nq2);
+  //----------------------------------------------
+  // Define solution to be projected
+  for(i = 0; i < nq1*nq2; ++i)
+  {
+      sol[i]  = Tri_sol(x[i],y[i],order,order);
+  }
+  //----------------------------------------------
+  
+  Array<OneD, NekDouble> esol(order*(order+1)/2);
+  Array<OneD, NekDouble> coeffs(order*(order+1)/2);
+
+  //---------------------------------------------
+  // Interpolate to equispaced points
+  E->PhysInterpToSimplexEquiSpaced(sol,esol,order);
+  //---------------------------------------------
+
+  //--------------------------------------------
+  // Project from equispaced points back to coeffs
+  E->EquiSpacedToCoeffs(esol,coeffs);
+  //--------------------------------------------
+
+  Array<OneD,NekDouble> phys = Array<OneD,NekDouble>(nq1*nq2);
+  //--------------------------------------------
+  // Project from equispaced points back to coeffs
+  E->BwdTrans(coeffs,phys);
+  //--------------------------------------------
+  
+  //--------------------------------------------
+  // Calculate L_inf error
+  cout << "L infinity error: " << E->Linf(phys,sol) << endl;
+  cout << "L 2 error:        " << E->L2  (phys,sol) << endl;
+  //--------------------------------------------  
+}
+
+NekDouble Tri_sol(NekDouble x, NekDouble y, int order1, int order2){
+    int    l,k;
+    NekDouble sol = 0;
+
+    for(k = 0; k < order1; ++k)
+    {
+        for(l = 0; l < order2-k; ++l)
+        {
+            sol += pow(x,k)*pow(y,l);
+        }
+    }
+
+    return sol;
+}