md = im.setflowequation(md, mdl_odr, 'all')
md.flowequation.fe_HO = 'P1'
## set for no-slip basal velocity BC (replaced with high friction above) :
#basal_v = md.mesh.vertexonbase
#md.stressbalance.spcvx[basal_v] = 0.0
#md.stressbalance.spcvy[basal_v] = 0.0
#md.stressbalance.spcvz[basal_v] = 0.0
#===============================================================================
# solve :
print_text('::: issm -- solving :::', 'red')
md.cluster = im.generic('name', im.gethostname(), 'np', 1)
md.verbose = im.verbose('convergence', True)
if tmc: md = im.solve(md, 'SteadyState')
else: md = im.solve(md, 'StressBalance')
#===============================================================================
# plot the results :
print_text('::: issm -- plotting :::', 'red')
p = md.results.StressbalanceSolution.Pressure[md.mesh.vertexonbase]
u_x = md.results.StressbalanceSolution.Vx[md.mesh.vertexonsurface]
u_y = md.results.StressbalanceSolution.Vy[md.mesh.vertexonsurface]
u_z = md.results.StressbalanceSolution.Vz[md.mesh.vertexonsurface]
u = np.array([u_x.flatten(), u_y.flatten(), u_z.flatten()])
# save the mesh coordinates and data for interpolation with CSLVR :
np.savetxt(out_dir + 'x.txt', md.mesh.x2d)
np.savetxt(out_dir + 'y.txt', md.mesh.y2d)
md.transient.requested_outputs = [
'default', 'GroundedArea', 'FloatingArea', 'IceVolume',
'IceVolumeAboveFloatation'
]
#===============================================================================
print_text('::: issm -- set boundary conditions :::', 'red')
# Set the default boundary conditions for an ice-sheet :
#md = im.SetMarineIceSheetBC(md) # create placeholder arrays for indicies
md.extrude(6, 1.0)
md = im.setflowequation(md, mdl_odr, 'all')
md.flowequation.fe_HO = 'P1'
#===============================================================================
# save the state of the model :
#im.savevars(out_dir + 'mismip_init.md', 'md', md)
#===============================================================================
# solve :
print_text('::: issm -- solving :::', 'red')
md.cluster = im.generic('name', im.gethostname(), 'np', 4)
md.verbose = im.verbose('solution', True, 'control', True, 'convergence', True)
md = im.solve(md, 'Transient')
#===============================================================================
# save the state of the model :
im.savevars(out_dir + 'mismip_zero_stress.md', 'md', md)
# extrude the mesh so that there are 5 cells in height :
md.extrude(6, 1.0)
# set the flow equation of type `mdl_odr` defined above :
md = im.setflowequation(md, mdl_odr, 'all')
md.flowequation.fe_HO = 'P1'
#===============================================================================
# solve :
print_text('::: issm -- solving initial velocity :::', 'red')
md.cluster = im.generic('name', im.gethostname(), 'np', 1)
md.verbose = im.verbose('convergence', True)
md = im.solve(md, 'Stressbalance')
#===============================================================================
# FIXME: since the model was extruded, we have to re-define the element-wise
# multiplicative identities. This is not ideal :
# rank-zero tensor vertex ones vector :
v_ones = np.ones(md.mesh.numberofvertices)
# rank-zero tensor element ones vector :
e_ones = np.ones(md.mesh.numberofelements)
# rank-two tensor ones vector :
A_ones = np.ones((md.mesh.numberofvertices, 6))
# n has one value per element :
md.materials.rheology_n = n * np.ones(md.mesh.numberofelements)
#===============================================================================
# solve steady-state solution :
print_text('::: issm -- solving :::', 'red')
# solver parameters :
md.stressbalance.restol = 0.01
md.stressbalance.reltol = 0.1
md.stressbalance.abstol = np.nan
md.stressbalance.isnewton = 1
md.cluster = im.generic('name', im.gethostname(), 'np', 1)
md.verbose = im.verbose('convergence', True)
md = im.solve(md, 'Stressbalance')
#===============================================================================
# data assimilation :
md.inversion.iscontrol = 1 # Do inversion? 1 = yes; 0 = no
md.inversion.incomplete_adjoint = 1 # 1 = linear viscosity; 0 = non-linear visc
# set the control parameter, either 'FrictionCoefficient'
# or 'MaterialsRheologyBar' :
md.inversion.control_parameters = ['FrictionCoefficient']
md.inversion.nsteps = 100 # number of inversion steps
# Original value was 0.5 :
md.inversion.step_threshold = 0.001 * np.ones(md.inversion.nsteps)
# original value was 5 :