def checkCFL(solution, dx, courant, time, tEND):
"""Return dt and boolean value
Check CFL stability and final time matching
>>> checkCFL([1,1,1,1,0,0,0,0], 0.5, 1, 1, 3,)
0.5, False
>>> checkCFL([1,1,1,1,0,0,0,0], 0.5, 1, 2.5, 3,)
0.5, False
>>> checkCFL([1,1,1,1,0,0,0,0], 0.5, 1, 2.6, 3,)
0.5, False
dt = c * dx / max( abs( eigenvalue(q) ) );
if(time + dt > t1)
dt = t1-time;
end
if(time >= t1)
break
end"""
maxflux = np.max(np.abs(flx.eigenvalue(solution)))
dt = courant * dx / maxflux
# if dt == np.nan: return dt, False
if time + dt > tEND:
return tEND - time, False
if time >= tEND:
return -9999, False
# strformat = 'time={t:6.5f}; dt={dt:6.5f}; dx={dx:6.5f}; c={c:3.2f}; maxflux={fl:6.5f};'
# print(strformat.format(t=time, dt=dt, dx=dx, c=courant, fl=maxflux) )
# return dt and stop
return dt, True
def g(q, xi):
"""
function y = g(q,xi)
y = eigenvalue(q)-xi;
"""
return flx.eigenvalue(q)-xi