Changeset 3120 in Sophya for trunk/Cosmo/SimLSS/genefluct3d.cc

Timestamp:

Dec 21, 2006, 4:45:09 PM (19 years ago)

Author:

cmv

Message:

Suite de la mise dans la base cvs cmv 21/12/2006

File:

• trunk/Cosmo/SimLSS/genefluct3d.cc (modified) (2 diffs)

trunk/Cosmo/SimLSS/genefluct3d.cc

@@ -344 +344 @@
 void GeneFluct3D::FilterByPixel(void)
 // Filtrage par la fonction fenetre du pixel (parallelepipede)
-// TF = 1/(dx*dy*dz)*Int[{0,dx},{0,dy},{0,dz}]
+// TF = 1/(dx*dy*dz)*Int[{-dx/2,dx/2},{-dy/2,dy/2},{-dz/2,dz/2}]
 //                   e^(ik_x*x) e^(ik_y*y) e^(ik_z*z) dxdydz
-// |TF|^2 = 2*(1-cos(k_x*dx)/dx^2/k_x^2 * (idem dy) * (idem dz)
-// et on traite la divergence en K_x = 0:
-// 2*(1-cos(k*d)/d^2/k^2 ~= 1 - (k*d)^2/12 *[1 - (k*d)^2/30]
+//    = 2/(k_x*dx) * sin(k_x*dx/2)  * (idem y) * (idem z)
+// Gestion divergence en 0: sin(y)/y = 1 - y^2/6*(1-y^2/20)
+//                          avec y = k_x*dx/2
 {
  int lp=2;
@@ -355 +355 @@
  for(int i=0;i<Nx_;i++) {
    int ii = (i>Nx_/2) ? Nx_-i : i;
-   double kx = ii*Dkx_ *Dx_;
-   double pkx2 = pixelfilter(kx); 
+   double kx = ii*Dkx_ *Dx_/2;
+   double pkx = pixelfilter(kx); 
    for(int j=0;j<Ny_;j++) {
      int jj = (j>Ny_/2) ? Ny_-j : j;
-     double ky = jj*Dky_ *Dy_;
-     double pky2 =  pixelfilter(ky); 
+     double ky = jj*Dky_ *Dy_/2;
+     double pky =  pixelfilter(ky); 
      for(int l=0;l<NCz_;l++) {
-       double kz = l*Dkz_ *Dz_;
-       double pkz2 =  pixelfilter(kz); 
-       T_(l,j,i) *= pkx2*pky2*pkz2;
+       double kz = l*Dkz_ *Dz_/2;
+       double pkz =  pixelfilter(kz);
+       T_(l,j,i) *= pkx*pky*pkz;
      }
    }