Merge branch 'RemoveEntropicSRT' into 'master'

Remove entropic srt

See merge request pycodegen/lbmpy!121

lbmpy/creationfunctions.py

@@ -73,7 +73,6 @@ from lbmpy.methods.creationfunctions import CollisionSpaceInfo
 from lbmpy.methods.creationfunctions import (
     create_with_monomial_cumulants, create_with_polynomial_cumulants, create_with_default_polynomial_cumulants)
 from lbmpy.methods.momentbased.entropic import add_entropy_condition, add_iterative_entropy_condition
-from lbmpy.methods.momentbased.entropic_eq_srt import create_srt_entropic
 from lbmpy.relaxationrates import relaxation_rate_from_magic_number
 from lbmpy.simplificationfactory import create_simplification_strategy
 from lbmpy.stencils import LBStencil
@@ -375,7 +374,7 @@ class LBMConfig:
             elif not self.collision_space_info.collision_space.compatible(self.method):
                 raise ValueError("Given method is not compatible with given collision space.")
         else:
-            if self.method in {Method.SRT, Method.TRT, Method.ENTROPIC_SRT,
+            if self.method in {Method.SRT, Method.TRT,
                                Method.TRT_KBC_N1, Method.TRT_KBC_N2, Method.TRT_KBC_N3, Method.TRT_KBC_N4}:
                 self.collision_space_info = CollisionSpaceInfo(CollisionSpace.POPULATIONS)
             elif self.entropic or self.fluctuating:
@@ -572,7 +571,6 @@ def create_lb_update_rule(collision_rule=None, lbm_config=None, lbm_optimisation
         dst_field = src_field.new_field_with_different_name(lbm_config.temporary_field_name)
 
     kernel_type = lbm_config.kernel_type
-    update_rule = None
     if kernel_type == 'stream_pull_only':
         update_rule = create_stream_pull_with_output_kernel(lb_method, src_field, dst_field, lbm_config.output)
     else:
@@ -607,7 +605,6 @@ def create_lb_collision_rule(lb_method=None, lbm_config=None, lbm_optimisation=N
         lb_method = create_lb_method(lbm_config)
 
     cqc = lb_method.conserved_quantity_computation
-
     rho_in = lbm_config.density_input
     u_in = lbm_config.velocity_input
 
@@ -618,7 +615,6 @@ def create_lb_collision_rule(lb_method=None, lbm_config=None, lbm_optimisation=N
 
     pre_simplification = lbm_optimisation.pre_simplification
     if rho_in is not None or u_in is not None:
-        cqc = lb_method.conserved_quantity_computation
         cqe = cqc.equilibrium_input_equations_from_pdfs(lb_method.pre_collision_pdf_symbols)
         cqe_main_assignments = cqe.main_assignments_dict
 
@@ -667,7 +663,6 @@ def create_lb_collision_rule(lb_method=None, lbm_config=None, lbm_optimisation=N
                                            omega_output_field=lbm_config.omega_output_field)
 
     if lbm_config.output:
-        cqc = lb_method.conserved_quantity_computation
         output_eqs = cqc.output_equations_from_pdfs(lb_method.pre_collision_pdf_symbols, lbm_config.output)
         collision_rule = collision_rule.new_merged(output_eqs)
 
@@ -744,9 +739,6 @@ def create_lb_method(lbm_config=None, **params):
             raise NotImplementedError("KBC type TRT methods can only be constructed for D2Q9 and D3Q27 stencils")
         method_nr = lbm_config.method.name[-1]
         method = create_trt_kbc(dim, relaxation_rates[0], relaxation_rates[1], 'KBC-N' + method_nr, **common_params)
-    elif lbm_config.method == Method.ENTROPIC_SRT:
-        method = create_srt_entropic(lbm_config.stencil, relaxation_rates[0], lbm_config.force_model,
-                                     lbm_config.compressible)
     elif lbm_config.method == Method.CUMULANT:
         if lbm_config.nested_moments is not None:
             method = create_with_polynomial_cumulants(

lbmpy/enums.py

@@ -119,12 +119,6 @@ class Method(Enum):
     To get the entropic method also *entropic* needs to be set to `True`. 
     There are four KBC methods available in lbmpy. The naming is according to :cite:`karlin2015entropic`
     """
-    ENTROPIC_SRT = auto()
-    """
-    See :func:`lbmpy.methods.create_srt_entropic`,
-    An entropic version of the isothermal lattice Boltzmann method with the simplicity and 
-    computational efficiency of the standard lattice Boltzmann model. For details see :cite:`Ansumali2003`
-    """
     CUMULANT = auto()
     """
     See :func:`lbmpy.methods.create_with_default_polynomial_cumulants`
@@ -172,8 +166,7 @@ class CollisionSpace(Enum):
         """Determines if the given `lbmpy.enums.Method` is compatible with this collision space."""
         compat_dict = {
             CollisionSpace.POPULATIONS: {Method.SRT, Method.TRT, Method.MRT_RAW, Method.MRT,
-                                         Method.TRT_KBC_N1, Method.TRT_KBC_N2, Method.TRT_KBC_N3, Method.TRT_KBC_N4,
-                                         Method.ENTROPIC_SRT},
+                                         Method.TRT_KBC_N1, Method.TRT_KBC_N2, Method.TRT_KBC_N3, Method.TRT_KBC_N4},
             CollisionSpace.RAW_MOMENTS: {Method.SRT, Method.TRT, Method.MRT_RAW, Method.MRT},
             CollisionSpace.CENTRAL_MOMENTS: {Method.CENTRAL_MOMENT},
             CollisionSpace.CUMULANTS: {Method.MONOMIAL_CUMULANT, Method.CUMULANT}

lbmpy/methods/abstractlbmethod.py

@@ -111,7 +111,7 @@ class AbstractLbMethod(abc.ABC):
                 relaxation_rate = sp.sympify(relaxation_rate)
                 # special treatment for zero, sp.Zero would be an integer ..
                 if isinstance(relaxation_rate, Zero):
-                    relaxation_rate = sp.Number(0)
+                    relaxation_rate = 0.0
                 if not isinstance(relaxation_rate, sp.Symbol):
                     rt_symbol = sp.Symbol(f"rr_{len(subexpressions)}")
                     subexpressions[relaxation_rate] = rt_symbol

lbmpy/methods/centeredcumulant/centeredcumulantmethod.py

@@ -531,6 +531,10 @@ class CenteredCumulantBasedLbMethod(AbstractLbMethod):
         subexpressions += k_post_to_pdfs_eqs.subexpressions
         main_assignments = k_post_to_pdfs_eqs.main_assignments
 
+        simplification_hints = cqe.simplification_hints.copy()
+        simplification_hints.update(self._cqc.defined_symbols())
+        simplification_hints['relaxation_rates'] = [rr for rr in self.relaxation_rates]
+
         #   8) Maybe add forcing terms if CenteredCumulantForceModel was not used
         if self._force_model is not None and \
                 not isinstance(self._force_model, CenteredCumulantForceModel) and include_force_terms:
@@ -541,6 +545,7 @@ class CenteredCumulantBasedLbMethod(AbstractLbMethod):
             subexpressions += force_subexpressions
             main_assignments = [Assignment(eq.lhs, eq.rhs + force_term_symbol)
                                 for eq, force_term_symbol in zip(main_assignments, force_term_symbols)]
+            simplification_hints['force_terms'] = force_term_symbols
 
         #   Aaaaaand we're done.
-        return LbmCollisionRule(self, main_assignments, subexpressions)
+        return LbmCollisionRule(self, main_assignments, subexpressions, simplification_hints)

lbmpy/methods/creationfunctions.py

@@ -658,11 +658,11 @@ def _get_relaxation_info_dict(relaxation_rates, nested_moments, dim):
         for group in nested_moments:
             for moment in group:
                 if get_order(moment) <= 1:
-                    result[moment] = sp.Number(0)
+                    result[moment] = 0.0
                 elif is_shear_moment(moment, dim):
                     result[moment] = relaxation_rates[0]
                 else:
-                    result[moment] = sp.Number(1)
+                    result[moment] = 1.0
 
     # if relaxation rate for each moment is specified they are all used
     if len(relaxation_rates) == number_of_moments:
@@ -687,7 +687,7 @@ def _get_relaxation_info_dict(relaxation_rates, nested_moments, dim):
                 next_rr = False
                 for moment in group:
                     if get_order(moment) <= 1:
-                        result[moment] = sp.Number(0)
+                        result[moment] = 0.0
                     elif is_shear_moment(moment, dim):
                         result[moment] = shear_rr
                     elif is_bulk_moment(moment, dim):

lbmpy/methods/momentbased/__init__.py

 from lbmpy.methods.momentbased.momentbasedmethod import MomentBasedLbMethod
 from .centralmomentbasedmethod import CentralMomentBasedLbMethod
-from lbmpy.methods.momentbased.entropic_eq_srt import EntropicEquilibriumSRT
 
-__all__ = ["MomentBasedLbMethod", "CentralMomentBasedLbMethod", "EntropicEquilibriumSRT"]
+__all__ = ["MomentBasedLbMethod", "CentralMomentBasedLbMethod"]

lbmpy/methods/momentbased/centralmomentbasedmethod.py

@@ -359,6 +359,10 @@ class CentralMomentBasedLbMethod(AbstractLbMethod):
         subexpressions += c_post_to_pdfs_eqs.subexpressions
         main_assignments = c_post_to_pdfs_eqs.main_assignments
 
+        simplification_hints = cqe.simplification_hints.copy()
+        simplification_hints.update(self._cqc.defined_symbols())
+        simplification_hints['relaxation_rates'] = [rr for rr in self.relaxation_rates]
+
         #   5) Maybe add forcing terms.
         if include_force_terms and not moment_space_forcing:
             force_model_terms = self._force_model(self)
@@ -368,5 +372,6 @@ class CentralMomentBasedLbMethod(AbstractLbMethod):
             subexpressions += force_subexpressions
             main_assignments = [Assignment(eq.lhs, eq.rhs + force_term_symbol)
                                 for eq, force_term_symbol in zip(main_assignments, force_term_symbols)]
+            simplification_hints['force_terms'] = force_term_symbols
 
         return LbmCollisionRule(self, main_assignments, subexpressions)

lbmpy/methods/momentbased/entropic_eq_srt.py

-import sympy as sp
-
-from lbmpy.maxwellian_equilibrium import get_weights
-from lbmpy.methods.abstractlbmethod import AbstractLbMethod, LbmCollisionRule
-from lbmpy.methods.conservedquantitycomputation import DensityVelocityComputation
-from pystencils import Assignment, AssignmentCollection
-
-
-class EntropicEquilibriumSRT(AbstractLbMethod):
-    """
-    Equilibrium from 'Minimal entropic kinetic models for hydrodynamics' :cite:`Ansumali2003`
-    """
-
-    def __init__(self, stencil, relaxation_rate, force_model, conserved_quantity_calculation):
-        super(EntropicEquilibriumSRT, self).__init__(stencil)
-
-        self._cqc = conserved_quantity_calculation
-        self._weights = get_weights(stencil, c_s_sq=sp.Rational(1, 3))
-        self._relaxationRate = relaxation_rate
-        self._forceModel = force_model
-        self.shear_relaxation_rate = relaxation_rate
-
-    @property
-    def conserved_quantity_computation(self):
-        return self._cqc
-
-    @property
-    def weights(self):
-        return self._weights
-
-    @property
-    def relaxation_rates(self):
-        return tuple([self._relaxationRate for i in range(len(self.stencil))])
-
-    @property
-    def zeroth_order_equilibrium_moment_symbol(self, ):
-        return self._cqc.zeroth_order_moment_symbol
-
-    @property
-    def first_order_equilibrium_moment_symbols(self, ):
-        return self._cqc.first_order_moment_symbols
-
-    def get_equilibrium(self, conserved_quantity_equations=None, include_force_terms=False):
-        return self._get_collision_rule_with_relaxation_rate(1,
-                                                             conserved_quantity_equations=conserved_quantity_equations,
-                                                             include_force_terms=include_force_terms)
-
-    def get_equilibrium_terms(self):
-        equilibrium = self.get_equilibrium()
-        return sp.Matrix([eq.rhs for eq in equilibrium.main_assignments])
-
-    def _get_collision_rule_with_relaxation_rate(self, relaxation_rate, include_force_terms=True,
-                                                 conserved_quantity_equations=None):
-        f = sp.Matrix(self.pre_collision_pdf_symbols)
-        rho = self._cqc.zeroth_order_moment_symbol
-        u = self._cqc.first_order_moment_symbols
-
-        all_subexpressions = []
-        if self._forceModel is not None:
-            all_subexpressions += AssignmentCollection(self._forceModel.subs_dict_force).all_assignments
-
-        if conserved_quantity_equations is None:
-            conserved_quantity_equations = self._cqc.equilibrium_input_equations_from_pdfs(f, False)
-        all_subexpressions += conserved_quantity_equations.all_assignments
-
-        eq = []
-        for w_i, direction in zip(self.weights, self.stencil):
-            f_i = rho * w_i
-            for u_a, e_ia in zip(u, direction):
-                b = sp.sqrt(1 + 3 * u_a ** 2)
-                f_i *= (2 - b) * ((2 * u_a + b) / (1 - u_a)) ** e_ia
-            eq.append(f_i)
-
-        collision_eqs = [Assignment(lhs, (1 - relaxation_rate) * f_i + relaxation_rate * eq_i)
-                         for lhs, f_i, eq_i in zip(self.post_collision_pdf_symbols, self.pre_collision_pdf_symbols, eq)]
-
-        if (self._forceModel is not None) and include_force_terms:
-            force_model_terms = self._forceModel(self)
-            force_term_symbols = sp.symbols("forceTerm_:%d" % (len(force_model_terms, )))
-            force_subexpressions = [Assignment(sym, force_model_term)
-                                    for sym, force_model_term in zip(force_term_symbols, force_model_terms)]
-            all_subexpressions += force_subexpressions
-            collision_eqs = [Assignment(eq.lhs, eq.rhs + force_term_symbol)
-                             for eq, force_term_symbol in zip(collision_eqs, force_term_symbols)]
-        cr = LbmCollisionRule(self, collision_eqs, all_subexpressions)
-        cr.simplification_hints['relaxation_rates'] = []
-        return cr
-
-    def get_collision_rule(self, conserved_quantity_equations=None, pre_simplification=None):
-        return self._get_collision_rule_with_relaxation_rate(self._relaxationRate,
-                                                             conserved_quantity_equations=conserved_quantity_equations)
-
-
-def create_srt_entropic(stencil, relaxation_rate, force_model, compressible):
-    if not compressible:
-        raise NotImplementedError("entropic-srt only implemented for compressible models")
-    density_velocity_computation = DensityVelocityComputation(stencil, compressible, not compressible, force_model)
-
-    return EntropicEquilibriumSRT(stencil, relaxation_rate, force_model, density_velocity_computation)

lbmpy/phasefield_allen_cahn/contact_angle.py

@@ -7,6 +7,7 @@ from pystencils.boundaries.boundaryhandling import BoundaryOffsetInfo
 from pystencils.boundaries.boundaryconditions import Boundary
 
 from pystencils.typing import TypedSymbol
+from pystencils.typing import CastFunc
 
 
 class ContactAngle(Boundary):
@@ -42,7 +43,8 @@ class ContactAngle(Boundary):
             angle = TypedSymbol("a", self._data_type)
             tmp = TypedSymbol("tmp", self._data_type)
 
-            result = [SympyAssignment(tmp, sum([x * x for x in neighbor])), SympyAssignment(dist, 0.5 * sp.sqrt(tmp)),
+            result = [SympyAssignment(tmp, CastFunc(sum([x * x for x in neighbor]), self._data_type)),
+                      SympyAssignment(dist, 0.5 * sp.sqrt(tmp)),
                       SympyAssignment(angle, math.cos(math.radians(self._contact_angle)))]
 
             var = - dist * (4.0 / self._interface_width) * angle

lbmpy/simplificationfactory.py

@@ -66,6 +66,7 @@ def _moment_space_simplification(split_inner_loop):
     s = SimplificationStrategy()
     s.add(insert_constants)
     s.add(insert_aliases)
-    # s.add(insert_constants)
+    if split_inner_loop:
+        s.add(create_lbm_split_groups)
     s.add(lambda ac: ac.new_without_unused_subexpressions())
     return s

lbmpy_tests/test_entropic.py

+import platform
+
 import numpy as np
 import sympy as sp
 import pytest
 
-from lbmpy.enums import ForceModel, Method, Stencil
-from lbmpy.forcemodels import Guo
-from lbmpy.methods.momentbased.entropic_eq_srt import create_srt_entropic
+from lbmpy.enums import ForceModel, Method
 from lbmpy.scenarios import create_lid_driven_cavity
-from lbmpy.stencils import LBStencil
 
 
-@pytest.mark.parametrize('method', [Method.TRT_KBC_N1, Method.TRT_KBC_N2, Method.TRT_KBC_N3])
+@pytest.mark.parametrize('method', [Method.TRT_KBC_N1, Method.TRT_KBC_N2, Method.TRT_KBC_N3, Method.TRT_KBC_N4])
 def test_entropic_methods(method):
+    if platform.system().lower() == 'windows' and method == Method.TRT_KBC_N4:
+        pytest.skip("For some reason this test does not run on windows", allow_module_level=True)
+    
     sc_kbc = create_lid_driven_cavity((20, 20), method=method,
                                       relaxation_rates=[1.9999, sp.Symbol("omega_free")],
                                       entropic_newton_iterations=3, entropic=True, compressible=True,
@@ -18,20 +20,3 @@ def test_entropic_methods(method):
 
     sc_kbc.run(1000)
     assert np.isfinite(np.max(sc_kbc.velocity[:, :]))
-
-
-def test_entropic_srt():
-    stencil = LBStencil(Stencil.D2Q9)
-    relaxation_rate = 1.8
-    method = create_srt_entropic(stencil, relaxation_rate, Guo((0, 1e-6)), True)
-    assert method.zeroth_order_equilibrium_moment_symbol == sp.symbols("rho")
-    assert method.first_order_equilibrium_moment_symbols == sp.symbols("u_:2")
-
-    eq = method.get_equilibrium()
-    terms = method.get_equilibrium_terms()
-    rel = method.relaxation_rates
-
-    for i in range(len(terms)):
-        assert sp.simplify(eq.main_assignments[i].rhs - terms[i]) == 0
-        assert rel[i] == 1.8
-

lbmpy_tests/test_quicktests.py

@@ -13,7 +13,7 @@ def test_poiseuille_channel_quicktest():
 
 
 def test_entropic_methods():
-    sc_kbc = create_lid_driven_cavity((20, 20), method=Method.TRT_KBC_N4,
+    sc_kbc = create_lid_driven_cavity((40, 40), method=Method.TRT_KBC_N4,
                                       relaxation_rates=[1.9999, sp.Symbol("omega_free")],
                                       entropic_newton_iterations=3, entropic=True, compressible=True,
                                       zero_centered=False, force=(-1e-10, 0), force_model=ForceModel.LUO)
@@ -21,20 +21,14 @@ def test_entropic_methods():
     sc_srt = create_lid_driven_cavity((40, 40), relaxation_rate=1.9999, lid_velocity=0.05, compressible=True,
                                       zero_centered=False, force=(-1e-10, 0), force_model=ForceModel.LUO)
 
-    sc_entropic = create_lid_driven_cavity((40, 40), method=Method.ENTROPIC_SRT, relaxation_rate=1.9999,
-                                           lid_velocity=0.05, compressible=True, zero_centered=False,
-                                           force=(-1e-10, 0), force_model=ForceModel.LUO)
-
     sc_srt.run(1000)
     sc_kbc.run(1000)
-    sc_entropic.run(1000)
     assert np.isnan(np.max(sc_srt.velocity[:, :]))
     assert np.isfinite(np.max(sc_kbc.velocity[:, :]))
-    assert np.isfinite(np.max(sc_entropic.velocity[:, :]))
 
 
 def test_cumulant_ldc():
-    sc_cumulant = create_lid_driven_cavity((20, 20), method=Method.CUMULANT, relaxation_rate=1.999999,
+    sc_cumulant = create_lid_driven_cavity((40, 40), method=Method.CUMULANT, relaxation_rate=1.999999,
                                            compressible=True, force=(-1e-10, 0))
 
     sc_cumulant.run(100)