def mult(self, mat, x, y, inc=False):
with self.cfn.dat.vec as v:
x.copy(v)
firedrake.prolong(self.cfn, self.ffn)
for bc in self.fbcs:
bc.zero(self.ffn)
with self.ffn.dat.vec_ro as v:
if inc:
y.axpy(1.0, v)
else:
v.copy(y)
def mult(self, mat, x, y, inc=False):
with self.cfn.dat.vec as v:
x.copy(v)
firedrake.prolong(self.cfn, self.ffn)
for bc in self.fbcs:
bc.zero(self.ffn)
with self.ffn.dat.vec_ro as v:
if inc:
y.axpy(1.0, v)
else:
v.copy(y)
def prolong(c, f):
return firedrake.prolong(c, f)
def interpolate(self, vector, out):
Tc = vector.fun
for Tinter in self.intermediate_Ts:
fd.prolong(Tc, Tinter)
Tc = Tinter
fd.prolong(Tc, out)
def prolong(c, f):
return firedrake.prolong(c, f)
u_in = firedrake.Function(V_in)
input_name = os.path.splitext(args.input)[0]
with firedrake.DumbCheckpoint(input_name, mode=firedrake.FILE_READ) as chk:
timesteps, indices = chk.get_timesteps()
chk.set_timestep(timesteps[-1], idx=indices[-1])
chk.load(h_in, name='h')
chk.load(u_in, name='u')
if args.input_level < args.output_level:
# Prolong the input data to the output function space
h0 = firedrake.Function(Q)
u0 = firedrake.Function(V)
firedrake.prolong(h_in, h0)
firedrake.prolong(u_in, u0)
else:
h0 = h_in
u0 = u_in
# Otherwise create some rough initial data
else:
h0 = interpolate(Constant(100), Q)
s0 = icepack.compute_surface(h=h0, b=z_b)
u0 = solver.diagnostic_solve(velocity=interpolate(
as_vector((35 * x / Lx, 0)), V),
thickness=h0,
surface=s0,
fluidity=A,
friction=C)
# increase dt until error > error_threshold
while error < error_threshold:
# error < error_threshold so increase dt by small amount
dt = dt + step
# NB: prolong does not copy so we must re-assign ref sol.
fine = Function(V_fine).assign(ref)
# Run the simulation with this dt
try:
sol = solver_CG(mesh,
el=cell_type,
space=space,
deg=degree,
T=0.50,
dt=dt)
error = errornorm(ref, prolong(sol, fine))
except Exception:
# numerical instability occurred, exit with last stable dt
dt = dt - step
error = 1e10
print(
"For degree {}, the error is {} using a {} s timestep".format(
degree, error, dt))
# error > error_threshold,
print(
"Highest stable dt is {} s for a degree {} for a an error threshold of {}"
.format(dt, degree, error_threshold))
dts[i, j] = dt
print("------FINISHED------")
print(dts)
