*
Copyright (C) 1996 Leif Laaksonen, Dage Sundholm *
Copyright (C) 1996-2010 Jacek Kobus *
*
This program is free software; you can redistribute it and/or modify *
it under the terms of the GNU General Public License version 2 as *
published by the Free Software Foundation. *
*
### diffmu ###
This routine calculates
(\frac{\partial^2}{\partial\mu^2} +
b(\ni,\mu) \frac{\partial}{\partial \mu}) f(\ni,\mu)
Function f has been imersed in the array f(nni+8,nmu+8) in order
to calculated derivatives in all the grid points. Originally the
routine was used for a single grid of constatnt step size
hmu. Accordingly dmu array contained the first- and second-order
derivative coefficients (taken from the 8th-order Sterling
interpolation formula) multiplied by the b array.
To make the routine work in the multigrid case (ngrids.ne.1)
the values of dmu(k,imu) for
imu=iemu(1)-3 ... iemu(1)+3
imu=iemu(2)-3 ... iemu(2)+3
.
imu=iemu(ngrids-1)-3 ... iemu(ngrids-1)+3
must be prepared with derivative coefficients which are based on
other interpolation formulae taking into account different grid
density to the left and right of the grid boundaries. See prepfix
for detailes.
This routine calculates
{\partial^2 / \partial\mu^2 +
b(\ni,\mu) \partial / \partial \mu} f(\ni,\mu)
Function f has been imersed in the array f(nni+8,nmu+8) in order
to calculated derivatives in all the grid points.
Originally the routine was used for a single grid of constatnt step
size hmu. Accordingly dmu array contained the first- and second-order
derivative coefficients (taken from the 8th-order Sterling
interpolation formula) multiplied by the B array.
To make the routine work in the multigrid case (ngrids.ne.1!)
the values of dmu(k,imu) for
imu=iemu(1)-3 ... iemu(1)+3
imu=iemu(2)-3 ... iemu(2)+3
.
imu=iemu(ngrids-1)-3 ... iemu(ngrids-1)+3
must be prepared with derivative coefficients which are based on
other interpolation formula taking into account different grid
density to the left and right of the grid boundaries. See prepfix
for detailes.
$Id: difmu.f,v 1.4 2006/06/28 20:43:48 jkob Exp $ |