X1 = 0.
XN = 1.
n_nod = 100
n_el = n_nod - 1
coors = nm.linspace(X1, XN, n_nod).reshape((n_nod, 1))
conn = nm.arange(n_nod, dtype=nm.int32).repeat(2)[1:-1].reshape((-1, 2))
mat_ids = nm.zeros(n_nod - 1, dtype=nm.int32)
descs = ['1_2']
mesh = Mesh.from_data('uniform_1D{}'.format(n_nod), coors, None, [conn],
[mat_ids], descs)
# -----------------------------
# | Create problem components |
# -----------------------------
integral = Integral('i', order=approx_order * 2)
domain = FEDomain(domain_name, mesh)
omega = domain.create_region('Omega', 'all')
left = domain.create_region('Gamma1', 'vertices in x == %.10f' % X1, 'vertex')
right = domain.create_region('Gamma2', 'vertices in x == %.10f' % XN, 'vertex')
field = DGField('dgfu', nm.float64, 'scalar', omega, approx_order=approx_order)
u = FieldVariable('u', 'unknown', field, history=1)
v = FieldVariable('v', 'test', field, primary_var_name='u')
MassT = DotProductVolumeTerm("adv_vol(v, u)",
"v, u",
integral,
omega,
u=u,
v=v)
def main():
from sfepy import data_dir
parser = ArgumentParser(description=__doc__,
formatter_class=RawDescriptionHelpFormatter)
parser.add_argument('--version', action='version', version='%(prog)s')
parser.add_argument('--young',
metavar='float',
type=float,
action='store',
dest='young',
default=2000.0,
help=helps['young'])
parser.add_argument('--poisson',
metavar='float',
type=float,
action='store',
dest='poisson',
default=0.4,
help=helps['poisson'])
parser.add_argument('--load',
metavar='float',
type=float,
action='store',
dest='load',
default=-1000.0,
help=helps['load'])
parser.add_argument('--order',
metavar='int',
type=int,
action='store',
dest='order',
default=1,
help=helps['order'])
parser.add_argument('-r',
'--refine',
metavar='int',
type=int,
action='store',
dest='refine',
default=0,
help=helps['refine'])
parser.add_argument('-s',
'--show',
action="store_true",
dest='show',
default=False,
help=helps['show'])
parser.add_argument('-p',
'--probe',
action="store_true",
dest='probe',
default=False,
help=helps['probe'])
options = parser.parse_args()
assert_((0.0 < options.poisson < 0.5),
"Poisson's ratio must be in ]0, 0.5[!")
assert_((0 < options.order),
'displacement approximation order must be at least 1!')
output('using values:')
output(" Young's modulus:", options.young)
output(" Poisson's ratio:", options.poisson)
output(' vertical load:', options.load)
output('uniform mesh refinement level:', options.refine)
# Build the problem definition.
mesh = Mesh.from_file(data_dir + '/meshes/2d/its2D.mesh')
domain = FEDomain('domain', mesh)
if options.refine > 0:
for ii in range(options.refine):
output('refine %d...' % ii)
domain = domain.refine()
output('... %d nodes %d elements' %
(domain.shape.n_nod, domain.shape.n_el))
omega = domain.create_region('Omega', 'all')
left = domain.create_region('Left', 'vertices in x < 0.001', 'facet')
bottom = domain.create_region('Bottom', 'vertices in y < 0.001', 'facet')
top = domain.create_region('Top', 'vertex 2', 'vertex')
field = Field.from_args('fu',
nm.float64,
'vector',
omega,
approx_order=options.order)
u = FieldVariable('u', 'unknown', field)
v = FieldVariable('v', 'test', field, primary_var_name='u')
D = stiffness_from_youngpoisson(2, options.young, options.poisson)
asphalt = Material('Asphalt', D=D)
load = Material('Load', values={'.val': [0.0, options.load]})
integral = Integral('i', order=2 * options.order)
integral0 = Integral('i', order=0)
t1 = Term.new('dw_lin_elastic(Asphalt.D, v, u)',
integral,
omega,
Asphalt=asphalt,
v=v,
u=u)
t2 = Term.new('dw_point_load(Load.val, v)', integral0, top, Load=load, v=v)
eq = Equation('balance', t1 - t2)
eqs = Equations([eq])
xsym = EssentialBC('XSym', bottom, {'u.1': 0.0})
ysym = EssentialBC('YSym', left, {'u.0': 0.0})
ls = AutoDirect({})
nls_status = IndexedStruct()
nls = Newton({}, lin_solver=ls, status=nls_status)
pb = Problem('elasticity', equations=eqs)
pb.set_bcs(ebcs=Conditions([xsym, ysym]))
pb.set_solver(nls)
# Solve the problem.
state = pb.solve()
output(nls_status)
# Postprocess the solution.
out = state.create_output_dict()
out = stress_strain(out, pb, state, extend=True)
pb.save_state('its2D_interactive.vtk', out=out)
gdata = geometry_data['2_3']
nc = len(gdata.coors)
integral_vn = Integral('ivn',
coors=gdata.coors,
weights=[gdata.volume / nc] * nc)
nodal_stress(out, pb, state, integrals=Integrals([integral_vn]))
if options.probe:
# Probe the solution.
probes, labels = gen_lines(pb)
sfield = Field.from_args('sym_tensor',
nm.float64,
3,
omega,
approx_order=options.order - 1)
stress = FieldVariable('stress',
'parameter',
sfield,
primary_var_name='(set-to-None)')
strain = FieldVariable('strain',
'parameter',
sfield,
primary_var_name='(set-to-None)')
cfield = Field.from_args('component',
nm.float64,
1,
omega,
approx_order=options.order - 1)
component = FieldVariable('component',
'parameter',
cfield,
primary_var_name='(set-to-None)')
ev = pb.evaluate
order = 2 * (options.order - 1)
strain_qp = ev('ev_cauchy_strain.%d.Omega(u)' % order, mode='qp')
stress_qp = ev('ev_cauchy_stress.%d.Omega(Asphalt.D, u)' % order,
mode='qp',
copy_materials=False)
project_by_component(strain, strain_qp, component, order)
project_by_component(stress, stress_qp, component, order)
all_results = []
for ii, probe in enumerate(probes):
fig, results = probe_results(u, strain, stress, probe, labels[ii])
fig.savefig('its2D_interactive_probe_%d.png' % ii)
all_results.append(results)
for ii, results in enumerate(all_results):
output('probe %d:' % ii)
output.level += 2
for key, res in ordered_iteritems(results):
output(key + ':')
val = res[1]
output(' min: %+.2e, mean: %+.2e, max: %+.2e' %
(val.min(), val.mean(), val.max()))
output.level -= 2
if options.show:
# Show the solution. If the approximation order is greater than 1, the
# extra DOFs are simply thrown away.
from sfepy.postprocess.viewer import Viewer
view = Viewer('its2D_interactive.vtk')
view(vector_mode='warp_norm',
rel_scaling=1,
is_scalar_bar=True,
is_wireframe=True)
def make_l2_projection_data(target,
eval_data,
order=None,
ls=None,
nls_options=None):
"""
Project scalar data to a scalar `target` field variable using the
:math:`L^2` dot product.
Parameters
----------
target : FieldVariable instance
The target variable.
eval_data : callable or array
Either a material-like function `eval_data()`, or an array of values in
quadrature points that has to be reshapable to the shape required by
`order`.
order : int, optional
The quadrature order. If not given, it is set to
`2 * target.field.approx_order`.
"""
if order is None:
order = 2 * target.field.approx_order
integral = Integral('i', order=order)
un = FieldVariable('u', 'unknown', target.field)
v = FieldVariable('v', 'test', un.field, primary_var_name=un.name)
lhs = Term.new('dw_dot(v, %s)' % un.name,
integral,
un.field.region,
v=v,
**{un.name: un})
def _eval_data(ts, coors, mode, **kwargs):
if mode == 'qp':
if callable(eval_data):
val = eval_data(ts, coors, mode, **kwargs)
else:
val = eval_data.reshape((coors.shape[0], 1, 1))
return {'val': val}
m = Material('m', function=_eval_data)
rhs = Term.new('dw_volume_lvf(m.val, v)',
integral,
un.field.region,
m=m,
v=v)
eq = Equation('projection', lhs - rhs)
eqs = Equations([eq])
if ls is None:
ls = ScipyDirect({})
if nls_options is None:
nls_options = {}
nls_status = IndexedStruct()
nls = Newton(nls_options, lin_solver=ls, status=nls_status)
pb = Problem('aux', equations=eqs)
pb.set_solver(nls)
# This sets the un variable with the projection solution.
pb.solve(save_results=False)
# Copy the projection solution to target.
target.set_data(un())
if nls_status.condition != 0:
output('L2 projection: solver did not converge!')
def main():
from sfepy import data_dir
parser = ArgumentParser(description=__doc__,
formatter_class=RawDescriptionHelpFormatter)
parser.add_argument('--version', action='version', version='%(prog)s')
parser.add_argument('--diffusivity',
metavar='float',
type=float,
action='store',
dest='diffusivity',
default=1e-5,
help=helps['diffusivity'])
parser.add_argument('--ic-max',
metavar='float',
type=float,
action='store',
dest='ic_max',
default=2.0,
help=helps['ic_max'])
parser.add_argument('--order',
metavar='int',
type=int,
action='store',
dest='order',
default=2,
help=helps['order'])
parser.add_argument('-r',
'--refine',
metavar='int',
type=int,
action='store',
dest='refine',
default=0,
help=helps['refine'])
parser.add_argument('-p',
'--probe',
action="store_true",
dest='probe',
default=False,
help=helps['probe'])
parser.add_argument('-s',
'--show',
action="store_true",
dest='show',
default=False,
help=helps['show'])
options = parser.parse_args()
assert_((0 < options.order),
'temperature approximation order must be at least 1!')
output('using values:')
output(' diffusivity:', options.diffusivity)
output(' max. IC value:', options.ic_max)
output('uniform mesh refinement level:', options.refine)
mesh = Mesh.from_file(data_dir + '/meshes/3d/cylinder.mesh')
domain = FEDomain('domain', mesh)
if options.refine > 0:
for ii in range(options.refine):
output('refine %d...' % ii)
domain = domain.refine()
output('... %d nodes %d elements' %
(domain.shape.n_nod, domain.shape.n_el))
omega = domain.create_region('Omega', 'all')
left = domain.create_region('Left', 'vertices in x < 0.00001', 'facet')
right = domain.create_region('Right', 'vertices in x > 0.099999', 'facet')
field = Field.from_args('fu',
nm.float64,
'scalar',
omega,
approx_order=options.order)
T = FieldVariable('T', 'unknown', field, history=1)
s = FieldVariable('s', 'test', field, primary_var_name='T')
m = Material('m', diffusivity=options.diffusivity * nm.eye(3))
integral = Integral('i', order=2 * options.order)
t1 = Term.new('dw_diffusion(m.diffusivity, s, T)',
integral,
omega,
m=m,
s=s,
T=T)
t2 = Term.new('dw_dot(s, dT/dt)', integral, omega, s=s, T=T)
eq = Equation('balance', t1 + t2)
eqs = Equations([eq])
# Boundary conditions.
ebc1 = EssentialBC('T1', left, {'T.0': 2.0})
ebc2 = EssentialBC('T2', right, {'T.0': -2.0})
# Initial conditions.
def get_ic(coors, ic):
x, y, z = coors.T
return 2 - 40.0 * x + options.ic_max * nm.sin(4 * nm.pi * x / 0.1)
ic_fun = Function('ic_fun', get_ic)
ic = InitialCondition('ic', omega, {'T.0': ic_fun})
pb = Problem('heat', equations=eqs)
pb.set_bcs(ebcs=Conditions([ebc1, ebc2]))
pb.set_ics(Conditions([ic]))
state0 = pb.get_initial_state()
init_fun, prestep_fun, _poststep_fun = pb.get_tss_functions(state0)
ls = ScipyDirect({})
nls_status = IndexedStruct()
nls = Newton({'is_linear': True}, lin_solver=ls, status=nls_status)
tss = SimpleTimeSteppingSolver({
't0': 0.0,
't1': 100.0,
'n_step': 11
},
nls=nls,
context=pb,
verbose=True)
pb.set_solver(tss)
if options.probe:
# Prepare probe data.
probes, labels = gen_probes(pb)
ev = pb.evaluate
order = 2 * (options.order - 1)
gfield = Field.from_args('gu',
nm.float64,
'vector',
omega,
approx_order=options.order - 1)
dvel = FieldVariable('dvel',
'parameter',
gfield,
primary_var_name='(set-to-None)')
cfield = Field.from_args('gu',
nm.float64,
'scalar',
omega,
approx_order=options.order - 1)
component = FieldVariable('component',
'parameter',
cfield,
primary_var_name='(set-to-None)')
nls_options = {'eps_a': 1e-16, 'i_max': 1}
suffix = tss.ts.suffix
def poststep_fun(ts, vec):
_poststep_fun(ts, vec)
# Probe the solution.
dvel_qp = ev('ev_diffusion_velocity.%d.Omega(m.diffusivity, T)' %
order,
copy_materials=False,
mode='qp')
project_by_component(dvel,
dvel_qp,
component,
order,
nls_options=nls_options)
all_results = []
for ii, probe in enumerate(probes):
fig, results = probe_results(ii, T, dvel, probe, labels[ii])
all_results.append(results)
plt.tight_layout()
fig.savefig('time_poisson_interactive_probe_%s.png' %
(suffix % ts.step),
bbox_inches='tight')
for ii, results in enumerate(all_results):
output('probe %d (%s):' % (ii, probes[ii].name))
output.level += 2
for key, res in ordered_iteritems(results):
output(key + ':')
val = res[1]
output(' min: %+.2e, mean: %+.2e, max: %+.2e' %
(val.min(), val.mean(), val.max()))
output.level -= 2
else:
poststep_fun = _poststep_fun
pb.time_update(tss.ts)
state0.apply_ebc()
# This is required if {'is_linear' : True} is passed to Newton.
mtx = prepare_matrix(pb, state0)
pb.try_presolve(mtx)
tss_status = IndexedStruct()
tss(state0.get_vec(pb.active_only),
init_fun=init_fun,
prestep_fun=prestep_fun,
poststep_fun=poststep_fun,
status=tss_status)
output(tss_status)
if options.show:
plt.show()
def main():
parser = OptionParser(usage=usage, version='%prog')
parser.add_option('-d',
'--dims',
metavar='dims',
action='store',
dest='dims',
default='[1.0, 1.0]',
help=helps['dims'])
parser.add_option('-c',
'--centre',
metavar='centre',
action='store',
dest='centre',
default='[0.0, 0.0]',
help=helps['centre'])
parser.add_option('-s',
'--shape',
metavar='shape',
action='store',
dest='shape',
default='[11, 11]',
help=helps['shape'])
parser.add_option('-b',
'--bc-kind',
metavar='kind',
action='store',
dest='bc_kind',
choices=['free', 'clamped'],
default='free',
help=helps['bc_kind'])
parser.add_option('--young',
metavar='float',
type=float,
action='store',
dest='young',
default=6.80e+10,
help=helps['young'])
parser.add_option('--poisson',
metavar='float',
type=float,
action='store',
dest='poisson',
default=0.36,
help=helps['poisson'])
parser.add_option('--density',
metavar='float',
type=float,
action='store',
dest='density',
default=2700.0,
help=helps['density'])
parser.add_option('--order',
metavar='int',
type=int,
action='store',
dest='order',
default=1,
help=helps['order'])
parser.add_option('-n',
'--n-eigs',
metavar='int',
type=int,
action='store',
dest='n_eigs',
default=6,
help=helps['order'])
parser.add_option('',
'--show',
action="store_true",
dest='show',
default=False,
help=helps['show'])
options, args = parser.parse_args()
assert_((0.0 < options.poisson < 0.5),
"Poisson's ratio must be in ]0, 0.5[!")
assert_((0 < options.order),
'displacement approximation order must be at least 1!')
dims = nm.array(eval(options.dims), dtype=nm.float64)
dim = len(dims)
centre = nm.array(eval(options.centre), dtype=nm.float64)[:dim]
shape = nm.array(eval(options.shape), dtype=nm.int32)[:dim]
output('dimensions:', dims)
output('centre: ', centre)
output('shape: ', shape)
output('using values:')
output(" Young's modulus:", options.young)
output(" Poisson's ratio:", options.poisson)
output(' density:', options.density)
# Build the problem definition.
mesh = gen_block_mesh(dims, shape, centre, name='mesh')
domain = FEDomain('domain', mesh)
bbox = domain.get_mesh_bounding_box()
min_y, max_y = bbox[:, 1]
eps = 1e-8 * (max_y - min_y)
omega = domain.create_region('Omega', 'all')
bottom = domain.create_region('Bottom',
'vertices in (y < %.10f)' % (min_y + eps),
'facet')
field = Field.from_args('fu',
nm.float64,
'vector',
omega,
approx_order=options.order)
u = FieldVariable('u', 'unknown', field)
v = FieldVariable('v', 'test', field, primary_var_name='u')
mtx_d = stiffness_from_youngpoisson(dim, options.young, options.poisson)
m = Material('m', D=mtx_d, rho=options.density)
integral = Integral('i', order=2 * options.order)
t1 = Term.new('dw_lin_elastic(m.D, v, u)', integral, omega, m=m, v=v, u=u)
t2 = Term.new('dw_volume_dot(m.rho, v, u)', integral, omega, m=m, v=v, u=u)
eq1 = Equation('stiffness', t1)
eq2 = Equation('mass', t2)
lhs_eqs = Equations([eq1, eq2])
pb = Problem('modal', equations=lhs_eqs)
if options.bc_kind == 'free':
pb.time_update()
n_rbm = dim * (dim + 1) / 2
else:
fixed_b = EssentialBC('FixedB', bottom, {'u.all': 0.0})
pb.time_update(ebcs=Conditions([fixed_b]))
n_rbm = 0
pb.update_materials()
# Assemble stiffness and mass matrices.
mtx_k = eq1.evaluate(mode='weak', dw_mode='matrix', asm_obj=pb.mtx_a)
mtx_m = mtx_k.copy()
mtx_m.data[:] = 0.0
mtx_m = eq2.evaluate(mode='weak', dw_mode='matrix', asm_obj=mtx_m)
try:
eigs, svecs = sla.eigsh(mtx_k,
k=options.n_eigs + n_rbm,
M=mtx_m,
which='SM',
tol=1e-5,
maxiter=10000)
except sla.ArpackNoConvergence as ee:
eigs = ee.eigenvalues
svecs = ee.eigenvectors
output('only %d eigenvalues converged!' % len(eigs))
eigs = eigs[n_rbm:]
svecs = svecs[:, n_rbm:]
output('eigenvalues:', eigs)
output('eigen-frequencies:', nm.sqrt(eigs))
# Make full eigenvectors (add DOFs fixed by boundary conditions).
variables = pb.get_variables()
vecs = nm.empty((variables.di.ptr[-1], svecs.shape[1]), dtype=nm.float64)
for ii in xrange(svecs.shape[1]):
vecs[:, ii] = variables.make_full_vec(svecs[:, ii])
# Save the eigenvectors.
out = {}
state = pb.create_state()
for ii in xrange(eigs.shape[0]):
state.set_full(vecs[:, ii])
aux = state.create_output_dict()
strain = pb.evaluate('ev_cauchy_strain.i.Omega(u)',
integrals=Integrals([integral]),
mode='el_avg',
verbose=False)
out['u%03d' % ii] = aux.popitem()[1]
out['strain%03d' % ii] = Struct(mode='cell', data=strain)
pb.save_state('eigenshapes.vtk', out=out)
pb.save_regions_as_groups('regions')
if options.show:
# Show the solution. If the approximation order is greater than 1, the
# extra DOFs are simply thrown away.
from sfepy.postprocess.viewer import Viewer
from sfepy.postprocess.domain_specific import DomainSpecificPlot
scaling = 0.05 * dims.max() / nm.abs(vecs).max()
ds = {}
for ii in xrange(eigs.shape[0]):
pd = DomainSpecificPlot('plot_displacements', [
'rel_scaling=%s' % scaling, 'color_kind="tensors"',
'color_name="strain%03d"' % ii
])
ds['u%03d' % ii] = pd
view = Viewer('eigenshapes.vtk')
view(domain_specific=ds,
only_names=sorted(ds.keys()),
is_scalar_bar=False,
is_wireframe=True)
'fu': ('real', 6, 'Omega', 1, 'H1', 'shell10x'),
}
variables = {
'u': ('unknown field', 'fu', 0),
'v': ('test field', 'fu', 'u'),
}
ebcs = {
'fix': ('Gamma1', {
'u.all': 0.0
}),
}
# Custom integral.
aux = Integral('i', order=3)
qp_coors, qp_weights = aux.get_qp('3_8')
qp_coors[:, 2] = thickness * (qp_coors[:, 2] - 0.5)
qp_weights *= thickness
integrals = {
'i': ('custom', qp_coors, qp_weights),
}
equations = {
'elasticity':
"""dw_shell10x.i.Omega(m.D, m.drill, v, u)
= dw_point_load.i.Gamma2(load.val, v)""",
}
solvers = {
def _gen_common_data(orders, gels, report):
import sfepy
from sfepy.base.base import Struct
from sfepy.linalg import combine
from sfepy.discrete import FieldVariable, Integral
from sfepy.discrete.fem import Mesh, FEDomain, Field
from sfepy.discrete.common.global_interp import get_ref_coors
bases = ([ii for ii in combine([['2_4', '3_8'],
['lagrange', 'serendipity', 'bernstein',
'lobatto']])]
+ [ii for ii in combine([['2_3', '3_4'],
['lagrange', 'bernstein']])])
for geom, poly_space_base in bases:
order = orders[geom]
if (geom == '3_8') and (poly_space_base == 'serendipity'):
order = 2
report('geometry: %s, base: %s, order: %d'
% (geom, poly_space_base, order))
integral = Integral('i', order=order)
aux = '' if geom in ['2_4', '3_8'] else 'z'
mesh0 = Mesh.from_file('meshes/elements/%s_2%s.mesh' % (geom, aux),
prefix_dir=sfepy.data_dir)
if (geom == '3_8'):
meshes = _permute_quad_face(mesh0)
else:
meshes = [mesh0]
gel = gels[geom]
perms = gel.get_conn_permutations()
qps, qp_weights = integral.get_qp(gel.surface_facet.name)
zz = nm.zeros_like(qps[:, :1])
qps = nm.hstack(([qps] + [zz]))
shift = shifts[geom]
rcoors = nm.ascontiguousarray(qps
+ shift[:1, :] - shift[1:, :])
ccoors = nm.ascontiguousarray(qps
+ shift[:1, :] + shift[1:, :])
all_oris = _get_possible_oris(geom)
oris = set()
for (ir, pr), (ic, pc), (im, mesh0) in product(
enumerate(perms), enumerate(perms), enumerate(meshes),
):
report('im: %d, ir: %d, ic: %d' % (im, ir, ic))
report('pr: %s, pc: %s' % (pr, pc))
mesh = mesh0.copy()
conn = mesh.cmesh.get_conn(mesh0.cmesh.tdim, 0).indices
conn = conn.reshape((mesh0.n_el, -1))
conn[0, :] = conn[0, pr]
conn[1, :] = conn[1, pc]
conn2 = mesh.get_conn(gel.name)
assert_((conn == conn2).all())
cache = Struct(mesh=mesh)
domain = FEDomain('domain', mesh)
omega = domain.create_region('Omega', 'all')
region = domain.create_region('Facet', rsels[geom], 'facet')
field = Field.from_args('f', nm.float64, shape=1,
region=omega, approx_order=order,
poly_space_base=poly_space_base)
fis = region.get_facet_indices()
conn = mesh.cmesh.get_conn_as_graph(region.dim,
region.dim - 1)
_oris = mesh.cmesh.facet_oris[conn.indptr[fis[:, 0]]
+ fis[:, 1]]
oris |= set(_oris)
if oris == all_oris:
break
var = FieldVariable('u', 'unknown', field)
report('# dofs: %d' % var.n_dof)
vec = nm.empty(var.n_dof, dtype=var.dtype)
ps = field.poly_space
dofs = field.get_dofs_in_region(region, merge=False)
edofs, fdofs = nm.unique(dofs[1]), nm.unique(dofs[2])
rrc, rcells, rstatus = get_ref_coors(field, rcoors,
cache=cache)
crc, ccells, cstatus = get_ref_coors(field, ccoors,
cache=cache)
assert_((rstatus == 0).all() and (cstatus == 0).all())
yield (geom, poly_space_base, qp_weights, mesh, im, ir, ic,
field, ps, rrc, rcells[0], crc, ccells[0],
vec, edofs, fdofs)
def main():
from sfepy import data_dir
parser = ArgumentParser()
parser.add_argument('--version', action='version', version='%(prog)s')
parser.add_argument('-s',
'--show',
action="store_true",
dest='show',
default=False,
help=helps['show'])
options = parser.parse_args()
mesh = Mesh.from_file(data_dir + '/meshes/2d/rectangle_tri.mesh')
domain = FEDomain('domain', mesh)
min_x, max_x = domain.get_mesh_bounding_box()[:, 0]
eps = 1e-8 * (max_x - min_x)
omega = domain.create_region('Omega', 'all')
gamma1 = domain.create_region('Gamma1',
'vertices in x < %.10f' % (min_x + eps),
'facet')
gamma2 = domain.create_region('Gamma2',
'vertices in x > %.10f' % (max_x - eps),
'facet')
field = Field.from_args('fu', nm.float64, 'vector', omega, approx_order=2)
u = FieldVariable('u', 'unknown', field)
v = FieldVariable('v', 'test', field, primary_var_name='u')
m = Material('m', D=stiffness_from_lame(dim=2, lam=1.0, mu=1.0))
f = Material('f', val=[[0.02], [0.01]])
integral = Integral('i', order=3)
t1 = Term.new('dw_lin_elastic(m.D, v, u)', integral, omega, m=m, v=v, u=u)
t2 = Term.new('dw_volume_lvf(f.val, v)', integral, omega, f=f, v=v)
eq = Equation('balance', t1 + t2)
eqs = Equations([eq])
fix_u = EssentialBC('fix_u', gamma1, {'u.all': 0.0})
bc_fun = Function('shift_u_fun', shift_u_fun, extra_args={'shift': 0.01})
shift_u = EssentialBC('shift_u', gamma2, {'u.0': bc_fun})
ls = ScipyDirect({})
nls_status = IndexedStruct()
nls = Newton({}, lin_solver=ls, status=nls_status)
pb = Problem('elasticity', equations=eqs, nls=nls, ls=ls)
pb.save_regions_as_groups('regions')
pb.time_update(ebcs=Conditions([fix_u, shift_u]))
vec = pb.solve()
print(nls_status)
pb.save_state('linear_elasticity.vtk', vec)
if options.show:
view = Viewer('linear_elasticity.vtk')
view(vector_mode='warp_norm',
rel_scaling=2,
is_scalar_bar=True,
is_wireframe=True)
def _gen_common_data(orders, gels, report):
import sfepy
from sfepy.base.base import Struct
from sfepy.linalg import combine
from sfepy.discrete import FieldVariable, Integral
from sfepy.discrete.fem import Mesh, FEDomain, Field
from sfepy.discrete.common.global_interp import get_ref_coors
bases = ([ii
for ii in combine([['2_4', '3_8'], ['lagrange', 'lobatto']])] +
[ii for ii in combine([['2_3', '3_4'], ['lagrange']])])
for geom, poly_space_base in bases:
report('geometry: %s, base: %s' % (geom, poly_space_base))
order = orders[geom]
integral = Integral('i', order=order)
aux = '' if geom in ['2_4', '3_8'] else 'z'
mesh0 = Mesh.from_file('meshes/elements/%s_2%s.mesh' % (geom, aux),
prefix_dir=sfepy.data_dir)
gel = gels[geom]
perms = gel.get_conn_permutations()
qps, qp_weights = integral.get_qp(gel.surface_facet.name)
zz = nm.zeros_like(qps[:, :1])
qps = nm.hstack(([qps] + [zz]))
shift = shifts[geom]
rcoors = nm.ascontiguousarray(qps + shift[:1, :] - shift[1:, :])
ccoors = nm.ascontiguousarray(qps + shift[:1, :] + shift[1:, :])
for ir, pr in enumerate(perms):
for ic, pc in enumerate(perms):
report('ir: %d, ic: %d' % (ir, ic))
report('pr: %s, pc: %s' % (pr, pc))
mesh = mesh0.copy()
conn = mesh.get_conn(gel.name)
conn[0, :] = conn[0, pr]
conn[1, :] = conn[1, pc]
cache = Struct(mesh=mesh)
domain = FEDomain('domain', mesh)
omega = domain.create_region('Omega', 'all')
region = domain.create_region('Facet', rsels[geom], 'facet')
field = Field.from_args('f',
nm.float64,
shape=1,
region=omega,
approx_order=order,
poly_space_base=poly_space_base)
var = FieldVariable('u', 'unknown', field)
report('# dofs: %d' % var.n_dof)
vec = nm.empty(var.n_dof, dtype=var.dtype)
ap = field.ap
ps = ap.interp.poly_spaces['v']
dofs = field.get_dofs_in_region(region, merge=False)
edofs, fdofs = nm.unique(dofs[1]), nm.unique(dofs[2])
rrc, rcells, rstatus = get_ref_coors(field,
rcoors,
cache=cache)
crc, ccells, cstatus = get_ref_coors(field,
ccoors,
cache=cache)
assert_((rstatus == 0).all() and (cstatus == 0).all())
yield (geom, poly_space_base, qp_weights, mesh, ir, ic, ap, ps,
rrc, rcells[0], crc, ccells[0], vec, edofs, fdofs)
bot = domain.create_region('Bot', 'vertices in z < %.10f' % (min_z + eps),
'vertex')
top = domain.create_region('Top', 'vertices in z > %.10f' % (max_z - eps),
'vertex')
field = Field.from_args('fu', np.float64, 'vector', omega, approx_order=1)
u = FieldVariable('u', 'unknown', field)
v = FieldVariable('v', 'test', field, primary_var_name='u')
# these are for stainless steel 316L
m = Material('m',
D=stiffness_from_youngpoisson(dim=3, young=1.93e9, poisson=0.275),
rho=8000.0)
integral = Integral('i', order=1)
t1 = Term.new('dw_lin_elastic(m.D, v, u)', integral, omega, m=m, v=v, u=u)
eq1 = Equation('balance_of_forces', t1)
eqs = Equations([eq1])
# materials = {
# 'solid': ({'K': 1e3, # bulk modulus
# 'mu': 20e0, # shear modulus of neoHookean term
# 'kappa': 10e0, # shear modulus of Mooney-Rivlin term
# },),
# }
# equations = {
# 'balance': """dw_ul_he_neohook.3.Omega( solid.mu, v, u )
# + dw_ul_he_mooney_rivlin.3.Omega(solid.kappa, v, u)
# + dw_ul_bulk_penalty.3.Omega( solid.K, v, u )
def eval_in_els_and_qp(expression, iels, coors,
fields, materials, variables,
functions=None, mode='eval', term_mode=None,
extra_args=None, active_only=True, verbose=True,
kwargs=None):
"""
Evaluate an expression in given elements and points.
Parameters
----------
expression : str
The expression to evaluate.
fields : dict
The dictionary of fields used in `variables`.
materials : Materials instance
The materials used in the expression.
variables : Variables instance
The variables used in the expression.
functions : Functions instance, optional
The user functions for materials etc.
mode : one of 'eval', 'el_avg', 'qp'
The evaluation mode - 'qp' requests the values in quadrature points,
'el_avg' element averages and 'eval' means integration over
each term region.
term_mode : str
The term call mode - some terms support different call modes
and depending on the call mode different values are
returned.
extra_args : dict, optional
Extra arguments to be passed to terms in the expression.
active_only : bool
If True, in 'weak' mode, the (tangent) matrices and residual
vectors (right-hand sides) contain only active DOFs.
verbose : bool
If False, reduce verbosity.
kwargs : dict, optional
The variables (dictionary of (variable name) : (Variable
instance)) to be used in the expression.
Returns
-------
out : array
The result of the evaluation.
"""
weights = nm.ones_like(coors[:, 0])
integral = Integral('ie', coors=coors, weights=weights)
domain = list(fields.values())[0].domain
region = Region('Elements', 'given elements', domain, '')
region.cells = iels
region.update_shape()
domain.regions.append(region)
for field in six.itervalues(fields):
field.clear_mappings(clear_all=True)
field.clear_qp_base()
aux = create_evaluable(expression, fields, materials,
variables.itervalues(), Integrals([integral]),
functions=functions, mode=mode,
extra_args=extra_args, active_only=active_only,
verbose=verbose, kwargs=kwargs)
equations, variables = aux
out = eval_equations(equations, variables,
preserve_caches=False,
mode=mode, term_mode=term_mode,
active_only=active_only)
domain.regions.pop()
return out
def run(domain, order):
omega = domain.create_region('Omega', 'all')
bbox = domain.get_mesh_bounding_box()
min_x, max_x = bbox[:, 0]
min_y, max_y = bbox[:, 1]
eps = 1e-8 * (max_x - min_x)
gamma1 = domain.create_region('Gamma1',
'vertices in (x < %.10f)' % (min_x + eps),
'facet')
gamma2 = domain.create_region('Gamma2',
'vertices in (x > %.10f)' % (max_x - eps),
'facet')
gamma3 = domain.create_region('Gamma3',
'vertices in y < %.10f' % (min_y + eps),
'facet')
gamma4 = domain.create_region('Gamma4',
'vertices in y > %.10f' % (max_y - eps),
'facet')
field = Field.from_args('fu', nm.float64, 1, omega, approx_order=order)
u = FieldVariable('u', 'unknown', field)
v = FieldVariable('v', 'test', field, primary_var_name='u')
integral = Integral('i', order=2 * order)
t1 = Term.new('dw_laplace(v, u)', integral, omega, v=v, u=u)
eq = Equation('eq', t1)
eqs = Equations([eq])
fix1 = EssentialBC('fix1', gamma1, {'u.0': 0.4})
fix2 = EssentialBC('fix2', gamma2, {'u.0': 0.0})
def get_shift(ts, coors, region):
return nm.ones_like(coors[:, 0])
dof_map_fun = Function('dof_map_fun', per.match_x_line)
shift_fun = Function('shift_fun', get_shift)
sper = LinearCombinationBC('sper', [gamma3, gamma4], {'u.0': 'u.0'},
dof_map_fun,
'shifted_periodic',
arguments=(shift_fun, ))
ls = ScipyDirect({})
pb = Problem('laplace', equations=eqs, auto_solvers=None)
pb.time_update(ebcs=Conditions([fix1, fix2]), lcbcs=Conditions([sper]))
ev = pb.get_evaluator()
nls = Newton({},
lin_solver=ls,
fun=ev.eval_residual,
fun_grad=ev.eval_tangent_matrix)
pb.set_solver(nls)
state = pb.solve()
return pb, state
def main():
parser = ArgumentParser(description=__doc__)
parser.add_argument('--version', action='version', version='%(prog)s')
parser.add_argument('-b',
'--basis',
metavar='name',
action='store',
dest='basis',
default='lagrange',
help=helps['basis'])
parser.add_argument('-n',
'--max-order',
metavar='order',
type=int,
action='store',
dest='max_order',
default=10,
help=helps['max_order'])
parser.add_argument('-m',
'--matrix',
metavar='type',
action='store',
dest='matrix_type',
default='laplace',
help=helps['matrix_type'])
parser.add_argument('-g',
'--geometry',
metavar='name',
action='store',
dest='geometry',
default='2_4',
help=helps['geometry'])
options = parser.parse_args()
dim, n_ep = int(options.geometry[0]), int(options.geometry[2])
output('reference element geometry:')
output(' dimension: %d, vertices: %d' % (dim, n_ep))
n_c = {'laplace': 1, 'elasticity': dim}[options.matrix_type]
output('matrix type:', options.matrix_type)
output('number of variable components:', n_c)
output('polynomial space:', options.basis)
output('max. order:', options.max_order)
mesh = Mesh.from_file(data_dir +
'/meshes/elements/%s_1.mesh' % options.geometry)
domain = FEDomain('domain', mesh)
omega = domain.create_region('Omega', 'all')
orders = nm.arange(1, options.max_order + 1, dtype=nm.int)
conds = []
order_fix = 0 if options.geometry in ['2_4', '3_8'] else 1
for order in orders:
output('order:', order, '...')
field = Field.from_args('fu',
nm.float64,
n_c,
omega,
approx_order=order,
space='H1',
poly_space_base=options.basis)
to = field.approx_order
quad_order = 2 * (max(to - order_fix, 0))
output('quadrature order:', quad_order)
integral = Integral('i', order=quad_order)
qp, _ = integral.get_qp(options.geometry)
output('number of quadrature points:', qp.shape[0])
u = FieldVariable('u', 'unknown', field)
v = FieldVariable('v', 'test', field, primary_var_name='u')
m = Material('m', D=stiffness_from_lame(dim, 1.0, 1.0), mu=1.0)
if options.matrix_type == 'laplace':
term = Term.new('dw_laplace(m.mu, v, u)',
integral,
omega,
m=m,
v=v,
u=u)
n_zero = 1
else:
assert_(options.matrix_type == 'elasticity')
term = Term.new('dw_lin_elastic(m.D, v, u)',
integral,
omega,
m=m,
v=v,
u=u)
n_zero = (dim + 1) * dim / 2
term.setup()
output('assembling...')
tt = time.clock()
mtx, iels = term.evaluate(mode='weak', diff_var='u')
output('...done in %.2f s' % (time.clock() - tt))
mtx = mtx[0, 0]
try:
assert_(nm.max(nm.abs(mtx - mtx.T)) < 1e-10)
except:
from sfepy.base.base import debug
debug()
output('matrix shape:', mtx.shape)
eigs = eig(mtx, method='eig.sgscipy', eigenvectors=False)
eigs.sort()
# Zero 'true' zeros.
eigs[:n_zero] = 0.0
ii = nm.where(eigs < 0.0)[0]
if len(ii):
output('matrix is not positive semi-definite!')
ii = nm.where(eigs[n_zero:] < 1e-12)[0]
if len(ii):
output('matrix has more than %d zero eigenvalues!' % n_zero)
output('smallest eigs:\n', eigs[:10])
ii = nm.where(eigs > 0.0)[0]
emin, emax = eigs[ii[[0, -1]]]
output('min:', emin, 'max:', emax)
cond = emax / emin
conds.append(cond)
output('condition number:', cond)
output('...done')
plt.figure(1)
plt.semilogy(orders, conds)
plt.xticks(orders, orders)
plt.xlabel('polynomial order')
plt.ylabel('condition number')
plt.grid()
plt.figure(2)
plt.loglog(orders, conds)
plt.xticks(orders, orders)
plt.xlabel('polynomial order')
plt.ylabel('condition number')
plt.grid()
plt.show()
def main(argv):
if argv is None:
argv = sys.argv[1:]
args = parser.parse_args(argv)
# vvvvvvvvvvvvvvvv #
approx_order = 2
# ^^^^^^^^^^^^^^^^ #
# Setup output names
outputs_folder = "../outputs"
domain_name = "domain_1D"
problem_name = "iburgers_1D"
output_folder = pjoin(outputs_folder, problem_name, str(approx_order))
output_format = "vtk"
save_timestn = 100
clear_folder(pjoin(output_folder, "*." + output_format))
configure_output({
'output_screen':
True,
'output_log_name':
pjoin(output_folder, f"last_run_{problem_name}_{approx_order}.txt")
})
# ------------
# | Get mesh |
# ------------
X1 = 0.
XN = 1.
n_nod = 100
n_el = n_nod - 1
mesh = get_gen_1D_mesh_hook(X1, XN, n_nod).read(None)
# -----------------------------
# | Create problem components |
# -----------------------------
integral = Integral('i', order=approx_order * 2)
domain = FEDomain(domain_name, mesh)
omega = domain.create_region('Omega', 'all')
left = domain.create_region('Gamma1', 'vertices in x == %.10f' % X1,
'vertex')
right = domain.create_region('Gamma2', 'vertices in x == %.10f' % XN,
'vertex')
field = DGField('dgfu',
nm.float64,
'scalar',
omega,
approx_order=approx_order)
u = FieldVariable('u', 'unknown', field, history=1)
v = FieldVariable('v', 'test', field, primary_var_name='u')
MassT = DotProductVolumeTerm("adv_vol(v, u)",
"v, u",
integral,
omega,
u=u,
v=v)
velo = nm.array(1.0)
def adv_fun(u):
vu = velo.T * u[..., None]
return vu
def adv_fun_d(u):
v1 = velo.T * nm.ones(u.shape + (1, ))
return v1
burg_velo = velo.T / nm.linalg.norm(velo)
def burg_fun(u):
vu = burg_velo * u[..., None]**2
return vu
def burg_fun_d(u):
v1 = 2 * burg_velo * u[..., None]
return v1
StiffT = NonlinearScalarDotGradTerm("burgers_stiff(f, df, u, v)",
"fun , fun_d, u[-1], v",
integral,
omega,
u=u,
v=v,
fun=burg_fun,
fun_d=burg_fun_d)
alpha = Material('alpha', val=[.0])
# FluxT = AdvectDGFluxTerm("adv_lf_flux(a.val, v, u)", "a.val, v, u[-1]",
# integral, omega, u=u, v=v, a=a, alpha=alpha)
FluxT = NonlinearHyperbolicDGFluxTerm("burgers_lf_flux(f, df, u, v)",
"fun , fun_d, v, u[-1]",
integral,
omega,
u=u,
v=v,
fun=burg_fun,
fun_d=burg_fun_d)
eq = Equation('balance', MassT - StiffT + FluxT)
eqs = Equations([eq])
# ------------------------------
# | Create boundary conditions |
# ------------------------------
left_fix_u = EssentialBC('left_fix_u', left, {'u.all': 1.0})
right_fix_u = EssentialBC('right_fix_u', right, {'u.all': 0.0})
# ----------------------------
# | Create initial condition |
# ----------------------------
def ghump(x):
"""
Nice gaussian.
"""
return nm.exp(-200 * x**2)
def ic_wrap(x, ic=None):
return ghump(x - .3)
ic_fun = Function('ic_fun', ic_wrap)
ics = InitialCondition('ic', omega, {'u.0': ic_fun})
# ------------------
# | Create problem |
# ------------------
pb = Problem(problem_name,
equations=eqs,
conf=Struct(options={"save_times": save_timestn},
ics={},
ebcs={},
epbcs={},
lcbcs={},
materials={}),
active_only=False)
pb.setup_output(output_dir=output_folder, output_format=output_format)
pb.set_ics(Conditions([ics]))
# ------------------
# | Create limiter |
# ------------------
limiter = MomentLimiter1D
# ---------------------------
# | Set time discretization |
# ---------------------------
CFL = .2
max_velo = nm.max(nm.abs(velo))
t0 = 0
t1 = .2
dx = nm.min(mesh.cmesh.get_volumes(1))
dt = dx / max_velo * CFL / (2 * approx_order + 1)
tn = int(nm.ceil((t1 - t0) / dt))
dtdx = dt / dx
# ------------------
# | Create solver |
# ------------------
ls = ScipyDirect({})
nls_status = IndexedStruct()
nls = Newton({'is_linear': True}, lin_solver=ls, status=nls_status)
tss_conf = {
't0': t0,
't1': t1,
'n_step': tn,
'limiters': {
"dgfu": limiter
}
}
tss = TVDRK3StepSolver(tss_conf, nls=nls, context=pb, verbose=True)
# ---------
# | Solve |
# ---------
pb.set_solver(tss)
state_end = pb.solve()
output("Solved equation \n\n\t\t u_t - div(f(u))) = 0\n")
output(f"With IC: {ic_fun.name}")
# output("and EBCs: {}".format(pb.ebcs.names))
# output("and EPBCS: {}".format(pb.epbcs.names))
output("-------------------------------------")
output(f"Approximation order is {approx_order}")
output(f"Space divided into {mesh.n_el} cells, " +
f"{len(mesh.coors)} steps, step size is {dx}")
output(f"Time divided into {tn - 1} nodes, {tn} steps, step size is {dt}")
output(f"CFL coefficient was {CFL} and " +
f"order correction {1 / (2 * approx_order + 1)}")
output(f"Courant number c = max(abs(u)) * dt/dx = {max_velo * dtdx}")
output("------------------------------------------")
output(f"Time stepping solver is {tss.name}")
output(f"Limiter used: {limiter.name}")
output("======================================")
# ----------
# | Plot 1D|
# ----------
load_and_plot_fun(output_folder, domain_name, t0, t1,
min(tn, save_timestn), ic_fun)
def main():
parser = ArgumentParser(description=__doc__,
formatter_class=RawDescriptionHelpFormatter)
parser.add_argument('--version', action='version', version='%(prog)s')
parser.add_argument('-d', '--dims', metavar='dims',
action='store', dest='dims',
default='[1.0, 1.0]', help=helps['dims'])
parser.add_argument('-c', '--centre', metavar='centre',
action='store', dest='centre',
default='[0.0, 0.0]', help=helps['centre'])
parser.add_argument('-s', '--shape', metavar='shape',
action='store', dest='shape',
default='[11, 11]', help=helps['shape'])
parser.add_argument('-b', '--bc-kind', metavar='kind',
action='store', dest='bc_kind',
choices=['free', 'cantilever', 'fixed'],
default='free', help=helps['bc_kind'])
parser.add_argument('-a', '--axis', metavar='0, ..., dim, or -1',
type=int, action='store', dest='axis',
default=-1, help=helps['axis'])
parser.add_argument('--young', metavar='float', type=float,
action='store', dest='young',
default=6.80e+10, help=helps['young'])
parser.add_argument('--poisson', metavar='float', type=float,
action='store', dest='poisson',
default=0.36, help=helps['poisson'])
parser.add_argument('--density', metavar='float', type=float,
action='store', dest='density',
default=2700.0, help=helps['density'])
parser.add_argument('--order', metavar='int', type=int,
action='store', dest='order',
default=1, help=helps['order'])
parser.add_argument('-n', '--n-eigs', metavar='int', type=int,
action='store', dest='n_eigs',
default=6, help=helps['n_eigs'])
parser.add_argument('-i', '--ignore', metavar='int', type=int,
action='store', dest='ignore',
default=None, help=helps['ignore'])
parser.add_argument('--solver', metavar='solver', action='store',
dest='solver',
default= \
"eig.scipy,method:'eigh',tol:1e-5,maxiter:1000",
help=helps['solver'])
parser.add_argument('--show',
action="store_true", dest='show',
default=False, help=helps['show'])
parser.add_argument('filename', nargs='?', default=None)
options = parser.parse_args()
aux = options.solver.split(',')
kwargs = {}
for option in aux[1:]:
key, val = option.split(':')
kwargs[key.strip()] = eval(val)
eig_conf = Struct(name='evp', kind=aux[0], **kwargs)
output('using values:')
output(" Young's modulus:", options.young)
output(" Poisson's ratio:", options.poisson)
output(' density:', options.density)
output('displacement field approximation order:', options.order)
output('requested %d eigenvalues' % options.n_eigs)
output('using eigenvalue problem solver:', eig_conf.kind)
output.level += 1
for key, val in six.iteritems(kwargs):
output('%s: %r' % (key, val))
output.level -= 1
assert_((0.0 < options.poisson < 0.5),
"Poisson's ratio must be in ]0, 0.5[!")
assert_((0 < options.order),
'displacement approximation order must be at least 1!')
filename = options.filename
if filename is not None:
mesh = Mesh.from_file(filename)
dim = mesh.dim
dims = nm.diff(mesh.get_bounding_box(), axis=0)
else:
dims = nm.array(eval(options.dims), dtype=nm.float64)
dim = len(dims)
centre = nm.array(eval(options.centre), dtype=nm.float64)[:dim]
shape = nm.array(eval(options.shape), dtype=nm.int32)[:dim]
output('dimensions:', dims)
output('centre: ', centre)
output('shape: ', shape)
mesh = gen_block_mesh(dims, shape, centre, name='mesh')
output('axis: ', options.axis)
assert_((-dim <= options.axis < dim), 'invalid axis value!')
eig_solver = Solver.any_from_conf(eig_conf)
# Build the problem definition.
domain = FEDomain('domain', mesh)
bbox = domain.get_mesh_bounding_box()
min_coor, max_coor = bbox[:, options.axis]
eps = 1e-8 * (max_coor - min_coor)
ax = 'xyz'[:dim][options.axis]
omega = domain.create_region('Omega', 'all')
bottom = domain.create_region('Bottom',
'vertices in (%s < %.10f)'
% (ax, min_coor + eps),
'facet')
bottom_top = domain.create_region('BottomTop',
'r.Bottom +v vertices in (%s > %.10f)'
% (ax, max_coor - eps),
'facet')
field = Field.from_args('fu', nm.float64, 'vector', omega,
approx_order=options.order)
u = FieldVariable('u', 'unknown', field)
v = FieldVariable('v', 'test', field, primary_var_name='u')
mtx_d = stiffness_from_youngpoisson(dim, options.young, options.poisson)
m = Material('m', D=mtx_d, rho=options.density)
integral = Integral('i', order=2*options.order)
t1 = Term.new('dw_lin_elastic(m.D, v, u)', integral, omega, m=m, v=v, u=u)
t2 = Term.new('dw_volume_dot(m.rho, v, u)', integral, omega, m=m, v=v, u=u)
eq1 = Equation('stiffness', t1)
eq2 = Equation('mass', t2)
lhs_eqs = Equations([eq1, eq2])
pb = Problem('modal', equations=lhs_eqs)
if options.bc_kind == 'free':
pb.time_update()
n_rbm = dim * (dim + 1) // 2
elif options.bc_kind == 'cantilever':
fixed = EssentialBC('Fixed', bottom, {'u.all' : 0.0})
pb.time_update(ebcs=Conditions([fixed]))
n_rbm = 0
elif options.bc_kind == 'fixed':
fixed = EssentialBC('Fixed', bottom_top, {'u.all' : 0.0})
pb.time_update(ebcs=Conditions([fixed]))
n_rbm = 0
else:
raise ValueError('unsupported BC kind! (%s)' % options.bc_kind)
if options.ignore is not None:
n_rbm = options.ignore
pb.update_materials()
# Assemble stiffness and mass matrices.
mtx_k = eq1.evaluate(mode='weak', dw_mode='matrix', asm_obj=pb.mtx_a)
mtx_m = mtx_k.copy()
mtx_m.data[:] = 0.0
mtx_m = eq2.evaluate(mode='weak', dw_mode='matrix', asm_obj=mtx_m)
try:
eigs, svecs = eig_solver(mtx_k, mtx_m, options.n_eigs + n_rbm,
eigenvectors=True)
except sla.ArpackNoConvergence as ee:
eigs = ee.eigenvalues
svecs = ee.eigenvectors
output('only %d eigenvalues converged!' % len(eigs))
output('%d eigenvalues converged (%d ignored as rigid body modes)' %
(len(eigs), n_rbm))
eigs = eigs[n_rbm:]
svecs = svecs[:, n_rbm:]
omegas = nm.sqrt(eigs)
freqs = omegas / (2 * nm.pi)
output('number | eigenvalue | angular frequency '
'| frequency')
for ii, eig in enumerate(eigs):
output('%6d | %17.12e | %17.12e | %17.12e'
% (ii + 1, eig, omegas[ii], freqs[ii]))
# Make full eigenvectors (add DOFs fixed by boundary conditions).
variables = pb.get_variables()
vecs = nm.empty((variables.di.ptr[-1], svecs.shape[1]),
dtype=nm.float64)
for ii in range(svecs.shape[1]):
vecs[:, ii] = variables.make_full_vec(svecs[:, ii])
# Save the eigenvectors.
out = {}
state = pb.create_state()
for ii in range(eigs.shape[0]):
state.set_full(vecs[:, ii])
aux = state.create_output_dict()
strain = pb.evaluate('ev_cauchy_strain.i.Omega(u)',
integrals=Integrals([integral]),
mode='el_avg', verbose=False)
out['u%03d' % ii] = aux.popitem()[1]
out['strain%03d' % ii] = Struct(mode='cell', data=strain)
pb.save_state('eigenshapes.vtk', out=out)
pb.save_regions_as_groups('regions')
if len(eigs) and options.show:
# Show the solution. If the approximation order is greater than 1, the
# extra DOFs are simply thrown away.
from sfepy.postprocess.viewer import Viewer
from sfepy.postprocess.domain_specific import DomainSpecificPlot
scaling = 0.05 * dims.max() / nm.abs(vecs).max()
ds = {}
for ii in range(eigs.shape[0]):
pd = DomainSpecificPlot('plot_displacements',
['rel_scaling=%s' % scaling,
'color_kind="tensors"',
'color_name="strain%03d"' % ii])
ds['u%03d' % ii] = pd
view = Viewer('eigenshapes.vtk')
view(domain_specific=ds, only_names=sorted(ds.keys()),
is_scalar_bar=False, is_wireframe=True)
def test_solving(self):
from sfepy.base.base import IndexedStruct
from sfepy.discrete import (FieldVariable, Material, Problem, Function,
Equation, Equations, Integral)
from sfepy.discrete.conditions import Conditions, EssentialBC
from sfepy.terms import Term
from sfepy.solvers.ls import ScipyDirect
from sfepy.solvers.nls import Newton
from sfepy.mechanics.matcoefs import stiffness_from_lame
u = FieldVariable('u', 'unknown', self.field)
v = FieldVariable('v', 'test', self.field, primary_var_name='u')
m = Material('m', D=stiffness_from_lame(self.dim, 1.0, 1.0))
f = Material('f', val=[[0.02], [0.01]])
bc_fun = Function('fix_u_fun',
fix_u_fun,
extra_args={'extra_arg': 'hello'})
fix_u = EssentialBC('fix_u', self.gamma1, {'u.all': bc_fun})
shift_u = EssentialBC('shift_u', self.gamma2, {'u.0': 0.1})
integral = Integral('i', order=3)
t1 = Term.new('dw_lin_elastic(m.D, v, u)',
integral,
self.omega,
m=m,
v=v,
u=u)
t2 = Term.new('dw_volume_lvf(f.val, v)',
integral,
self.omega,
f=f,
v=v)
eq = Equation('balance', t1 + t2)
eqs = Equations([eq])
ls = ScipyDirect({})
nls_status = IndexedStruct()
nls = Newton({}, lin_solver=ls, status=nls_status)
pb = Problem('elasticity', equations=eqs)
## pb.save_regions_as_groups('regions')
pb.set_bcs(ebcs=Conditions([fix_u, shift_u]))
pb.set_solver(nls)
state = pb.solve()
name = op.join(self.options.out_dir, 'test_high_level_solving.vtk')
pb.save_state(name, state)
ok = nls_status.condition == 0
if not ok:
self.report('solver did not converge!')
_ok = state.has_ebc()
if not _ok:
self.report('EBCs violated!')
ok = ok and _ok
return ok
def _solve(self, property_array):
"""
Solve the Sfepy problem for one sample.
Args:
property_array: array of shape (n_x, n_y, 2) where the last
index is for Lame's parameter and shear modulus,
respectively.
Returns:
the strain field of shape (n_x, n_y, 2) where the last
index represents the x and y displacements
"""
shape = property_array.shape[:-1]
mesh = self._get_mesh(shape)
domain = Domain('domain', mesh)
region_all = domain.create_region('region_all', 'all')
field = Field.from_args(
'fu',
np.float64,
'vector',
region_all, # pylint: disable=no-member
approx_order=2)
u = FieldVariable('u', 'unknown', field)
v = FieldVariable('v', 'test', field, primary_var_name='u')
m = self._get_material(property_array, domain)
integral = Integral('i', order=4)
t1 = Term.new('dw_lin_elastic_iso(m.lam, m.mu, v, u)',
integral,
region_all,
m=m,
v=v,
u=u)
eq = Equation('balance_of_forces', t1)
eqs = Equations([eq])
epbcs, functions = self._get_periodicBCs(domain)
ebcs = self._get_displacementBCs(domain)
lcbcs = self._get_linear_combinationBCs(domain)
ls = ScipyDirect({})
pb = Problem('elasticity', equations=eqs, functions=functions)
pb.time_update(ebcs=ebcs, epbcs=epbcs, lcbcs=lcbcs)
ev = pb.get_evaluator()
nls = Newton({},
lin_solver=ls,
fun=ev.eval_residual,
fun_grad=ev.eval_tangent_matrix)
try:
pb.set_solvers_instances(ls, nls)
except AttributeError:
pb.set_solver(nls)
vec = pb.solve()
u = vec.create_output_dict()['u'].data
u_reshape = np.reshape(u, (tuple(x + 1 for x in shape) + u.shape[-1:]))
dims = domain.get_mesh_bounding_box().shape[1]
strain = np.squeeze(
pb.evaluate(
'ev_cauchy_strain.{dim}.region_all(u)'.format(dim=dims),
mode='el_avg',
copy_materials=False))
strain_reshape = np.reshape(strain, (shape + strain.shape[-1:]))
stress = np.squeeze(
pb.evaluate(
'ev_cauchy_stress.{dim}.region_all(m.D, u)'.format(dim=dims),
mode='el_avg',
copy_materials=False))
stress_reshape = np.reshape(stress, (shape + stress.shape[-1:]))
return strain_reshape, u_reshape, stress_reshape
def create_local_problem(omega_gi, order):
"""
Local problem definition using a domain corresponding to the global region
`omega_gi`.
"""
mesh = omega_gi.domain.mesh
# All tasks have the whole mesh.
bbox = mesh.get_bounding_box()
min_x, max_x = bbox[:, 0]
eps_x = 1e-8 * (max_x - min_x)
mesh_i = Mesh.from_region(omega_gi, mesh, localize=True)
domain_i = FEDomain('domain_i', mesh_i)
omega_i = domain_i.create_region('Omega', 'all')
gamma1_i = domain_i.create_region('Gamma1',
'vertices in (x < %.10f)' %
(min_x + eps_x),
'facet',
allow_empty=True)
gamma2_i = domain_i.create_region('Gamma2',
'vertices in (x > %.10f)' %
(max_x - eps_x),
'facet',
allow_empty=True)
field_i = Field.from_args('fu', nm.float64, 1, omega_i, approx_order=order)
output('number of local field DOFs:', field_i.n_nod)
u_i = FieldVariable('u_i', 'unknown', field_i)
v_i = FieldVariable('v_i', 'test', field_i, primary_var_name='u_i')
integral = Integral('i', order=2 * order)
mat = Material('m', lam=10, mu=5)
t1 = Term.new('dw_laplace(m.lam, v_i, u_i)',
integral,
omega_i,
m=mat,
v_i=v_i,
u_i=u_i)
def _get_load(coors):
val = nm.ones_like(coors[:, 0])
for coor in coors.T:
val *= nm.sin(4 * nm.pi * coor)
return val
def get_load(ts, coors, mode=None, **kwargs):
if mode == 'qp':
return {'val': _get_load(coors).reshape(coors.shape[0], 1, 1)}
load = Material('load', function=Function('get_load', get_load))
t2 = Term.new('dw_volume_lvf(load.val, v_i)',
integral,
omega_i,
load=load,
v_i=v_i)
eq = Equation('balance', t1 - 100 * t2)
eqs = Equations([eq])
ebc1 = EssentialBC('ebc1', gamma1_i, {'u_i.all': 0.0})
ebc2 = EssentialBC('ebc2', gamma2_i, {'u_i.all': 0.1})
pb = Problem('problem_i', equations=eqs, active_only=False)
pb.time_update(ebcs=Conditions([ebc1, ebc2]))
pb.update_materials()
return pb
def create_local_problem(omega_gi, orders):
"""
Local problem definition using a domain corresponding to the global region
`omega_gi`.
"""
order_u, order_p = orders
mesh = omega_gi.domain.mesh
# All tasks have the whole mesh.
bbox = mesh.get_bounding_box()
min_x, max_x = bbox[:, 0]
eps_x = 1e-8 * (max_x - min_x)
min_y, max_y = bbox[:, 1]
eps_y = 1e-8 * (max_y - min_y)
mesh_i = Mesh.from_region(omega_gi, mesh, localize=True)
domain_i = FEDomain('domain_i', mesh_i)
omega_i = domain_i.create_region('Omega', 'all')
gamma1_i = domain_i.create_region('Gamma1',
'vertices in (x < %.10f)' %
(min_x + eps_x),
'facet',
allow_empty=True)
gamma2_i = domain_i.create_region('Gamma2',
'vertices in (x > %.10f)' %
(max_x - eps_x),
'facet',
allow_empty=True)
gamma3_i = domain_i.create_region('Gamma3',
'vertices in (y < %.10f)' %
(min_y + eps_y),
'facet',
allow_empty=True)
field1_i = Field.from_args('fu',
nm.float64,
mesh.dim,
omega_i,
approx_order=order_u)
field2_i = Field.from_args('fp',
nm.float64,
1,
omega_i,
approx_order=order_p)
output('field 1: number of local DOFs:', field1_i.n_nod)
output('field 2: number of local DOFs:', field2_i.n_nod)
u_i = FieldVariable('u_i', 'unknown', field1_i, order=0)
v_i = FieldVariable('v_i', 'test', field1_i, primary_var_name='u_i')
p_i = FieldVariable('p_i', 'unknown', field2_i, order=1)
q_i = FieldVariable('q_i', 'test', field2_i, primary_var_name='p_i')
if mesh.dim == 2:
alpha = 1e2 * nm.array([[0.132], [0.132], [0.092]])
else:
alpha = 1e2 * nm.array([[0.132], [0.132], [0.132], [0.092], [0.092],
[0.092]])
mat = Material('m',
D=stiffness_from_lame(mesh.dim, lam=10, mu=5),
k=1,
alpha=alpha)
integral = Integral('i', order=2 * (max(order_u, order_p)))
t11 = Term.new('dw_lin_elastic(m.D, v_i, u_i)',
integral,
omega_i,
m=mat,
v_i=v_i,
u_i=u_i)
t12 = Term.new('dw_biot(m.alpha, v_i, p_i)',
integral,
omega_i,
m=mat,
v_i=v_i,
p_i=p_i)
t21 = Term.new('dw_biot(m.alpha, u_i, q_i)',
integral,
omega_i,
m=mat,
u_i=u_i,
q_i=q_i)
t22 = Term.new('dw_laplace(m.k, q_i, p_i)',
integral,
omega_i,
m=mat,
q_i=q_i,
p_i=p_i)
eq1 = Equation('eq1', t11 - t12)
eq2 = Equation('eq1', t21 + t22)
eqs = Equations([eq1, eq2])
ebc1 = EssentialBC('ebc1', gamma1_i, {'u_i.all': 0.0})
ebc2 = EssentialBC('ebc2', gamma2_i, {'u_i.0': 0.05})
def bc_fun(ts, coors, **kwargs):
val = 0.3 * nm.sin(4 * nm.pi * (coors[:, 0] - min_x) / (max_x - min_x))
return val
fun = Function('bc_fun', bc_fun)
ebc3 = EssentialBC('ebc3', gamma3_i, {'p_i.all': fun})
pb = Problem('problem_i', equations=eqs, active_only=False)
pb.time_update(ebcs=Conditions([ebc1, ebc2, ebc3]))
pb.update_materials()
return pb
