Department of Scientific Computing    Institute for Numerical Simulation    University of Bonn

Documentation

Download

Programming References

Bug Reports / Suggestions

FAQ

Authors

           

---

WT.cc

// Example for non-adaptive wavelet transforms

# include "UniformData.hpp"
# include "Function.hpp"

int debugRefine ;

int main() {
 Wavelets WC("Interpolet",4) ;
 
 int L=7 ;                         // maximal level of refinement
 int i,a[2]={0},e[2]={1<<L,1<<L} ; // dimensions of the grid
 int BC[2][2] ;
 for (i=0; i<2; i++) BC[i][0]=BC[i][1]=-1 ; //boundary condition identifiers

 UniformData<2> A(a,e,&WC), B(a,e,&WC), C(a,e,&WC) ; // allocation of uniform grid with 129x129 points

 GeneralRadialFunction<2> F ; //  a predefined very spiky function
 double p[4]={0.5,1e-8 , 3./9 , 4./9} ; 
 F.SetParameters(p)         ;
 
 A.SetBoundaryConditions(BC)  ;
 A.SetFunction(&F,false,true) ;  // A contains the nodal values of F on the 129x129 grid
                                 // more precisely: A contains the scaling function coefficients of the 
                                 // Interpolant of F w.r.t. to the 129x129 grid 
                                 // The scaling functions are defined just on the interval and 
                                 // don't have any homogeneous boundary conditions

 // compute the coefficients for the isotropic Meyer-wavelets
 B.MRATransform(&A) ;

 // compute the coefficients for the anisotropic wavelets, by a tensor product transform
 for (i=0; i<2; i++) C.ApplyOp((i==0) ? &A : &C, i,  TRANSFORM) ;

 // write
 A.WriteUDF("../../Data/Test/A") ;
 B.WriteUDF("../../Data/Test/B") ;
 C.WriteUDF("../../Data/Test/C") ;
}

---