diff options
Diffstat (limited to 'src/finishbrilldata.F')
| -rw-r--r-- | src/finishbrilldata.F | 53 |
1 files changed, 31 insertions, 22 deletions
diff --git a/src/finishbrilldata.F b/src/finishbrilldata.F index ee49b57..36060e9 100644 --- a/src/finishbrilldata.F +++ b/src/finishbrilldata.F @@ -1,3 +1,12 @@ +/*@@ + @file finishbrilldata.F + @date + @author Carsten Gundlach (Cactus 4, Miguel Alcubierre) + @desc + Reconstruct metric from conformal factor. + @enddesc + @version $Header$ +@@*/ #include "cctk.h" #include "cctk_Parameters.h" @@ -22,22 +31,22 @@ external brillq -C Numbers. +c Numbers. zero = 0.0D0 -C Set up grid size. +c Set up grid size. nx = cctk_lsh(1) ny = cctk_lsh(2) nz = cctk_lsh(3) -C Parameters. +c Parameters. rhofudge = brill_rhofudge -C Replace flat metric left over from elliptic solve by -C Brill metric calculated from q and Psi. +c Replace flat metric left over from elliptic solve by +c Brill metric calculated from q and Psi. do k=1,nz do j=1,ny @@ -55,31 +64,31 @@ C Brill metric calculated from q and Psi. psi4 = brillpsi(i,j,k)**4 e2q = dexp(2.d0*brillq(rho1,z1,phi)) -C Fudge division by rho^2 on axis. (Physically, y^/rho^2, -C x^2/rho^2 and xy/rho^2 are of course regular.) -C Transform Brills form of the physical metric to Cartesian -C coordinates via -C -C e^2q (drho^2 + dz^2) + rho^2 dphi^2 = -C e^2q (dx^2 + dy^2 + dz^2) + (1-e^2q) (xdy-ydx)^2/rho^2 -C -C The individual coefficients can be read off as +c Fudge division by rho^2 on axis. (Physically, y^/rho^2, +c x^2/rho^2 and xy/rho^2 are of course regular.) +c Transform Brills form of the physical metric to Cartesian +c coordinates via +c +c e^2q (drho^2 + dz^2) + rho^2 dphi^2 = +c e^2q (dx^2 + dy^2 + dz^2) + (1-e^2q) (xdy-ydx)^2/rho^2 +c +c The individual coefficients can be read off as if (rho1 .gt. rhofudge) then - gzz(i,j,k) = psi4*e2q gxx(i,j,k) = psi4*(e2q + (1.d0 - e2q)*y1**2/rho2) gyy(i,j,k) = psi4*(e2q + (1.d0 - e2q)*x1**2/rho2) + gzz(i,j,k) = psi4*e2q gxy(i,j,k) = - psi4*(1.d0 - e2q)*x1*y1/rho2 else -C This fudge assumes that q = O(rho^2) near the axis. Which -C it should be, or the data will be singular. +c This fudge assumes that q = O(rho^2) near the axis. Which +c it should be, or the data will be singular. - gzz(i,j,k) = psi4 - gxx(i,j,k) = psi4 - gyy(i,j,k) = psi4 + gxx(i,j,k) = psi4 + gyy(i,j,k) = psi4 + gzz(i,j,k) = psi4 gxy(i,j,k) = zero end if @@ -88,12 +97,12 @@ C it should be, or the data will be singular. end do end do -C In any case, +c In any case, gxz = zero gyz = zero -C Vanishing extrinsic curvature completes the Cauchy data. +c Vanishing extrinsic curvature completes the Cauchy data. kxx = zero kyy = zero |