Do not enforce symmetry on T: only the k>0 matter anyways

1 files changed, 7 insertions, 20 deletions

diff --git a/src/navier-stokes.c b/src/navier-stokes.c
index 78207e0..6e386a3 100644
--- a/src/navier-stokes.c
+++ b/src/navier-stokes.c
@@ -207,6 +207,7 @@ int quiet(
   double nu,
   double delta,
   double L,
+  uint64_t starting_time,
   _Complex double* u0,
   _Complex double* g,
   bool irreversible,
@@ -227,7 +228,7 @@ int quiet(
   copy_u(u, u0, K1, K2);
 
   // iterate
-  for(t=0;nsteps==0 || t<nsteps;t++){
+  for(t=starting_time;nsteps==0 || t<starting_time+nsteps;t++){
     ns_step(u, K1, K2, N1, N2, nu, delta, L, g, fft1, fft2, ifft, tmp1, tmp2, tmp3, irreversible);
   }
 
@@ -511,13 +512,6 @@ int ns_T(
   // inverse fft
   fftw_execute(ifft.fft_plan);
 
-  // enforce T(u,-k)=T(u,k)^*
-  for(kx=-K1;kx<=K1;kx++){
-    for(ky=-K2;ky<=K2;ky++){
-      ifft.fft[klookup(kx,ky,N1,N2)]=(ifft.fft[klookup(kx,ky,N1,N2)]+conj(ifft.fft[klookup(-kx,-ky,N1,N2)]))/2;
-    }
-  }
-
   return(0);
 }
 
@@ -534,13 +528,13 @@ int ns_T_nofft(
   int px,py;
   int qx,qy;
 
-  // loop over K's (needs N1>=4*K1+1 and N2>=4*K2+1)
-  if (N1<4*K1+1 || N2<4*K2+1){
-    fprintf(stderr,"error: N1 and N2 need t be >= 4*K1+1 and 4*K2+1 respectively\n");
+  // loop over K's (needs N1>=2*K1+1 and N2>=2*K2+1)
+  if (N1<2*K1+1 || N2<2*K2+1){
+    fprintf(stderr,"error: N1 and N2 need t be >= 2*K1+1 and 2*K2+1 respectively\n");
     return(-1);
   }
-  for(kx=-2*K1;kx<=2*K1;kx++){
-    for(ky=-2*K2;ky<=2*K2;ky++){
+  for(kx=-K1;kx<=K1;kx++){
+    for(ky=-K2;ky<=K2;ky++){
       // init
       out[klookup(kx,ky,N1,N2)]=0.;
 
@@ -558,13 +552,6 @@ int ns_T_nofft(
     }
   }
 
-  // enforce T(u,-k)=T(u,k)^*
-  for(kx=-K1;kx<=K1;kx++){
-    for(ky=-K2;ky<=K2;ky++){
-      out[klookup(kx,ky,N1,N2)]=(out[klookup(kx,ky,N1,N2)]+conj(out[klookup(-kx,-ky,N1,N2)]))/2;
-    }
-  }
-
   return 0;
 }