c
c =========================================================
subroutine flx2(ixy,maxmx,meqn,mbc,mx,q,maux,aux,f)
c =========================================================
c
c # Flux-function for the two-dimensional Euler equations.
c
c # The flux is computed in x-direction if ixy=1
c # or in y-direction if ixy=2.
c
c # Copyright (C) 2002 Ralf Deiterding
c # Brandenburgische Universitaet Cottbus
c
c # Copyright (C) 2003-2007 California Institute of Technology
c # Ralf Deiterding, ralf@cacr.caltech.edu
c
implicit double precision (a-h,o-z)
dimension q(1-mbc:maxmx+mbc, meqn)
dimension aux(1-mbc:maxmx+mbc, maux)
dimension f(1-mbc:maxmx+mbc, meqn)
common /param/ gamma,gamma1
c
if (ixy.eq.1) then
mu = 2
mv = 3
else
mu = 3
mv = 2
endif
c
do i=1-mbc,mx+mbc
u = q(i,mu)/q(i,1)
v = q(i,mv)/q(i,1)
p = gamma1*(q(i,4) - 0.5d0*q(i,1)*(u**2+v**2))
f(i,1) = q(i,mu)
f(i,mu) = u*q(i,mu)+p
f(i,mv) = v*q(i,mu)
f(i,4) = u*(q(i,4)+p)
enddo
c
return
end