lbmpy/phasefield_allen_cahn/phasefield_simplifications.py

-import sympy as sp
-
-from pystencils.simp import (
-    SimplificationStrategy, apply_to_all_assignments,
-    insert_aliases, insert_zeros, insert_constants)
-
-
-def create_phasefield_simplification_strategy(lb_method):
-    s = SimplificationStrategy()
-    expand = apply_to_all_assignments(sp.expand)
-
-    s.add(expand)
-
-    s.add(insert_zeros)
-    s.add(insert_aliases)
-    s.add(insert_constants)
-    s.add(lambda ac: ac.new_without_unused_subexpressions())
-
-    return s

lbmpy_tests/test_float_kernel.py

-import pytest
-
-import pystencils as ps
-
-from lbmpy.creationfunctions import create_lb_function, LBMConfig
-from lbmpy.enums import Method
-from lbmpy.scenarios import create_lid_driven_cavity
-
-
-@pytest.mark.parametrize('double_precision', [False, True])
-@pytest.mark.parametrize('method_enum', [Method.SRT, Method.CENTRAL_MOMENT, Method.CUMULANT])
-def test_creation(double_precision, method_enum):
-    """Simple test that makes sure that only float variables are created"""
-    lbm_config = LBMConfig(method=method_enum, relaxation_rate=1.5, compressible=True)
-    config = ps.CreateKernelConfig(data_type="float64" if double_precision else "float32",
-                                   default_number_float="float64" if double_precision else "float32")
-    func = create_lb_function(lbm_config=lbm_config, config=config)
-    code = ps.get_code_str(func)
-
-    if double_precision:
-        assert 'float' not in code
-        assert 'double' in code
-    else:
-        assert 'double' not in code
-        assert 'float' in code
-
-
-@pytest.mark.parametrize('double_precision', [False, True])
-@pytest.mark.parametrize('method_enum', [Method.SRT, Method.CENTRAL_MOMENT, Method.CUMULANT])
-def test_scenario(method_enum, double_precision):
-    lbm_config = LBMConfig(method=method_enum, relaxation_rate=1.45, compressible=True)
-    config = ps.CreateKernelConfig(data_type="float64" if double_precision else "float32",
-                                   default_number_float="float64" if double_precision else "float32")
-    sc = create_lid_driven_cavity((16, 16, 8), lbm_config=lbm_config, config=config)
-    sc.run(1)
-    code = ps.get_code_str(sc.ast)
-
-    if double_precision:
-        assert 'float' not in code
-        assert 'double' in code
-    else:
-        assert 'double' not in code
-        assert 'float' in code

noxfile.py

+from __future__ import annotations
+from typing import Sequence
+from argparse import ArgumentParser
+
+import os
+import nox
+import subprocess
+import re
+
+nox.options.sessions = ["lint", "typecheck"]
+
+
+def get_cuda_version(session: nox.Session) -> None | tuple[int, ...]:
+    query_args = ["nvcc", "--version"]
+
+    try:
+        query_result = subprocess.run(query_args, capture_output=True)
+    except FileNotFoundError:
+        return None
+
+    matches = re.findall(r"release \d+\.\d+", str(query_result.stdout))
+    if matches:
+        match = matches[0]
+        version_string = match.split()[-1]
+        try:
+            return tuple(int(v) for v in version_string.split("."))
+        except ValueError:
+            pass
+
+    session.warn("nvcc was found, but I am unable to determine the CUDA version.")
+    return None
+
+
+def install_cupy(
+    session: nox.Session, cupy_version: str, skip_if_no_cuda: bool = False
+):
+    if cupy_version is not None:
+        cuda_version = get_cuda_version(session)
+        if cuda_version is None or cuda_version[0] not in (11, 12):
+            if skip_if_no_cuda:
+                session.skip(
+                    "No compatible installation of CUDA found - Need either CUDA 11 or 12"
+                )
+            else:
+                session.warn(
+                    "Running without cupy: no compatbile installation of CUDA found. Need either CUDA 11 or 12."
+                )
+                return
+
+        cuda_major = cuda_version[0]
+        cupy_package = f"cupy-cuda{cuda_major}x=={cupy_version}"
+        session.install(cupy_package)
+
+
+def check_external_doc_dependencies(session: nox.Session):
+    dot_args = ["dot", "--version"]
+    try:
+        _ = subprocess.run(dot_args, capture_output=True)
+    except FileNotFoundError:
+        session.error(
+            "Unable to build documentation: "
+            "Command `dot` from the `graphviz` package (https://www.graphviz.org/) is not available"
+        )
+
+
+def editable_install(session: nox.Session, opts: Sequence[str] = ()):
+    if opts:
+        opts_str = "[" + ",".join(opts) + "]"
+    else:
+        opts_str = ""
+    session.install("-e", f".{opts_str}")
+
+
+def install_pystencils_master(session: nox.Session):
+    session.install("git+https://i10git.cs.fau.de/pycodegen/pystencils.git@master")
+
+
+def install_sympy_master(session: nox.Session):
+    session.install("--upgrade", "git+https://github.com/sympy/sympy.git@master")
+
+
+@nox.session(python="3.10", tags=["qa", "code-quality"])
+def lint(session: nox.Session):
+    """Lint code using flake8"""
+
+    session.install("flake8")
+    session.run("flake8", "src/lbmpy")
+
+
+@nox.session(python="3.10", tags=["qa", "code-quality"])
+def typecheck(session: nox.Session):
+    """Run MyPy for static type checking"""
+    editable_install(session)
+    session.install("mypy")
+    session.run("mypy", "src/lbmpy")
+
+
+def run_testsuite(session: nox.Session, coverage: bool = True):
+    num_cores = os.cpu_count()
+
+    args = [
+        "pytest",
+        "-v",
+        "-n",
+        str(num_cores),
+        "-m",
+        "not longrun",
+        "--html",
+        "test-report/index.html",
+        "--junitxml=report.xml",
+    ]
+
+    if coverage:
+        args += [
+            "--cov-report=term",
+            "--cov=.",
+        ]
+
+    session.run(*args)
+
+    if coverage:
+        session.run("coverage", "html")
+        session.run("coverage", "xml")
+
+
+@nox.session(python=["3.10", "3.11", "3.12", "3.13"])
+def testsuite_cpu(session: nox.Session):
+    install_pystencils_master(session)
+    editable_install(session, ["alltrafos", "use_cython", "interactive", "tests"])
+    run_testsuite(session, coverage=False)
+
+
+@nox.session(python=["3.10", "3.11", "3.12", "3.13"])
+@nox.parametrize("cupy_version", ["12", "13"], ids=["cupy12", "cupy13"])
+def testsuite_gpu(session: nox.Session, cupy_version: str | None):
+    install_cupy(session, cupy_version, skip_if_no_cuda=True)
+    install_pystencils_master(session)
+    editable_install(session, ["alltrafos", "use_cython", "interactive", "tests"])
+    run_testsuite(session)
+
+
+@nox.parametrize("cupy_version", [None, "12", "13"], ids=["cpu", "cupy12", "cupy13"])
+@nox.session(python="3.10", tags=["test"])
+def testsuite_pystencils2(session: nox.Session, cupy_version: str | None):
+    if cupy_version is not None:
+        install_cupy(session, cupy_version, skip_if_no_cuda=True)
+
+    session.install(
+        "git+https://i10git.cs.fau.de/pycodegen/pystencils.git@v2.0-dev"
+    )
+    editable_install(session, ["alltrafos", "use_cython", "interactive", "tests"])
+
+    run_testsuite(session)
+
+
+@nox.session
+def quicktest(session: nox.Session):
+    parser = ArgumentParser()
+    parser.add_argument(
+        "--sympy-master", action="store_true", help="Use latest SymPy master revision"
+    )
+    args = parser.parse_args(session.posargs)
+
+    install_pystencils_master(session)
+    editable_install(session)
+
+    if args.sympy_master:
+        install_sympy_master(session)
+
+    session.run("python", "quicktest.py")

pyproject.toml

+[project]
+name = "lbmpy"
+description = "Code Generation for Lattice Boltzmann Methods"
+dynamic = ["version"]
+readme = "README.md"
+authors = [
+    { name = "Martin Bauer" },
+    { name = "Markus Holzer" },
+    { name = "Frederik Hennig" },
+    { email = "cs10-codegen@fau.de" },
+]
+license = { file = "COPYING.txt" }
+requires-python = ">=3.10"
+dependencies = ["pystencils>=1.3", "sympy>=1.12", "numpy>=1.8.0", "appdirs", "joblib", "packaging"]
+classifiers = [
+    "Development Status :: 4 - Beta",
+    "Framework :: Jupyter",
+    "Topic :: Software Development :: Code Generators",
+    "Topic :: Scientific/Engineering :: Physics",
+    "Intended Audience :: Developers",
+    "Intended Audience :: Science/Research",
+    "License :: OSI Approved :: GNU Affero General Public License v3 or later (AGPLv3+)",
+]
+
+[project.urls]
+"Bug Tracker" = "https://i10git.cs.fau.de/pycodegen/lbmpy/-/issues"
+"Documentation" = "https://pycodegen.pages.i10git.cs.fau.de/lbmpy/"
+"Source Code" = "https://i10git.cs.fau.de/pycodegen/lbmpy"
+
+[project.optional-dependencies]
+gpu = ['cupy']
+alltrafos = ['islpy', 'py-cpuinfo']
+bench_db = ['blitzdb', 'pymongo', 'pandas']
+interactive = [
+    'matplotlib',
+    'ipy_table',
+    'imageio',
+    'jupyter',
+    'pyevtk',
+    'rich',
+    'graphviz',
+    'scipy',
+    'scikit-image'
+]
+use_cython = [
+    'Cython'
+]
+doc = [
+    'sphinx',
+    'sphinx_rtd_theme',
+    'nbsphinx',
+    'sphinxcontrib-bibtex',
+    'sphinx_autodoc_typehints',
+    'pandoc',
+]
+tests = [
+    'pytest',
+    'pytest-cov',
+    'pytest-html',
+    'ansi2html',
+    'pytest-xdist',
+    'flake8',
+    'nbformat',
+    'nbconvert',
+    'ipython',
+    'randomgen>=1.18',
+]
+
+[build-system]
+requires = [
+    "setuptools>=69",
+    "versioneer[toml]>=0.29",
+]
+build-backend = "setuptools.build_meta"
+
+[tool.setuptools.package-data]
+
+[tool.setuptools.packages.find]
+where = ["src"]
+include = ["lbmpy", "lbmpy.*"]
+namespaces = false
+
+[tool.versioneer]
+# See the docstring in versioneer.py for instructions. Note that you must
+# re-run 'versioneer.py setup' after changing this section, and commit the
+# resulting files.
+VCS = "git"
+style = "pep440"
+versionfile_source = "src/lbmpy/_version.py"
+versionfile_build = "lbmpy/_version.py"
+tag_prefix = "release/"
+parentdir_prefix = "lbmpy-"

pytest.ini

 [pytest]
+testpaths = src tests doc/notebooks
+pythonpath = src
 python_files = test_*.py *_test.py scenario_*.py
 norecursedirs = *.egg-info .git .cache .ipynb_checkpoints htmlcov
-addopts = --doctest-modules --durations=20  --cov-config pytest.ini
+addopts = 
+       --doctest-modules --durations=20
+       --cov-config pytest.ini
+       --ignore=src/lbmpy/custom_code_nodes.py
+       --ignore=src/lbmpy/lookup_tables.py
+       --ignore=src/lbmpy/phasefield_allen_cahn/contact_angle.py
 markers =
        longrun: tests only run at night since they have large execution time
-       notebook: jupyter notebooks
+       notebook: mark for notebooks
 # these warnings all come from third party libraries.
 filterwarnings =
        ignore:the imp module is deprecated in favour of importlib:DeprecationWarning
@@ -14,15 +21,19 @@ filterwarnings =
 
 [run]
 branch = True
-source = lbmpy
-         lbmpy_tests
+source = src/lbmpy
+         tests
 
 omit = doc/*
-       lbmpy_tests/*
+       tests/*
        setup.py
        conftest.py
        versioneer.py
-       lbmpy/_version.py
+       quicktest.py
+       noxfile.py
+       src/lbmpy/_version.py
+       src/lbmpy/_compat.py
+       venv/
 
 [report]
 exclude_lines =
@@ -35,6 +46,7 @@ exclude_lines =
        # Don't complain if tests don't hit defensive assertion code:
        raise AssertionError
        raise NotImplementedError
+       NotImplementedError()
        #raise ValueError
 
        # Don't complain if non-runnable code isn't run:
@@ -43,7 +55,7 @@ exclude_lines =
        if __name__ == .__main__.:
 
 skip_covered = True
-fail_under = 88
+fail_under = 87
 
 [html]
 directory = coverage_report

quicktest.py

+#!/usr/bin/env python3
+
+from contextlib import redirect_stdout
+import io
+from tests.test_quicktests import (
+    test_poiseuille_channel_quicktest,
+    test_entropic_methods,
+    test_cumulant_ldc
+)
+
+quick_tests = [
+    test_poiseuille_channel_quicktest,
+    test_entropic_methods,
+    test_cumulant_ldc,
+]
+
+if __name__ == "__main__":
+    print("Running lbmpy quicktests")
+    for qt in quick_tests:
+        print(f"   -> {qt.__name__}")
+        with redirect_stdout(io.StringIO()):
+            qt()

setup.cfg

-# See the docstring in versioneer.py for instructions. Note that you must
-# re-run 'versioneer.py setup' after changing this section, and commit the
-# resulting files.
-
-[versioneer]
-VCS = git
-style = pep440
-versionfile_source = lbmpy/_version.py
-versionfile_build = lbmpy/_version.py
-tag_prefix = release/
-parentdir_prefix = lbmpy-
\ No newline at end of file

setup.py

-import os
-import io
-from setuptools import setup, find_packages
-import distutils
-from contextlib import redirect_stdout
-from importlib import import_module
+from setuptools import setup, __version__ as setuptools_version
 
-import versioneer
-
-try:
-    import cython  # noqa
-
-    USE_CYTHON = True
-except ImportError:
-    USE_CYTHON = False
-
-quick_tests = [
-    'test_quicktests.test_poiseuille_channel_quicktest',
-    'test_quicktests.test_entropic_methods',
-    'test_quicktests.test_cumulant_ldc',
-]
-
-
-class SimpleTestRunner(distutils.cmd.Command):
-    """A custom command to run selected tests"""
-
-    description = 'run some quick tests'
-    user_options = []
-
-    @staticmethod
-    def _run_tests_in_module(test):
-        """Short test runner function - to work also if py.test is not installed."""
-        test = 'lbmpy_tests.' + test
-        mod, function_name = test.rsplit('.', 1)
-        if isinstance(mod, str):
-            mod = import_module(mod)
+if int(setuptools_version.split('.')[0]) < 61:
+    raise Exception(
+        "[ERROR] lbmpy requires at least setuptools version 61 to install.\n"
+        "If this error occurs during an installation via pip, it is likely that there is a conflict between "
+        "versions of setuptools installed by pip and the system package manager. "
+        "In this case, it is recommended to install lbmpy into a virtual environment instead."
+    )
 
-        func = getattr(mod, function_name)
-        with redirect_stdout(io.StringIO()):
-            func()
-
-    def initialize_options(self):
-        pass
-
-    def finalize_options(self):
-        pass
-
-    def run(self):
-        """Run command."""
-        for test in quick_tests:
-            self._run_tests_in_module(test)
-
-
-def readme():
-    with open('README.md') as f:
-        return f.read()
-
-
-def cython_extensions(*extensions):
-    from distutils.extension import Extension
-    if USE_CYTHON:
-        ext = '.pyx'
-        result = [Extension(e, [os.path.join(*e.split(".")) + ext]) for e in extensions]
-        from Cython.Build import cythonize
-        result = cythonize(result, language_level=3)
-        return result
-    elif all([os.path.exists(os.path.join(*e.split(".")) + '.c') for e in extensions]):
-        ext = '.c'
-        result = [Extension(e, [os.path.join(*e.split(".")) + ext]) for e in extensions]
-        return result
-    else:
-        return None
+import versioneer
 
 
 def get_cmdclass():
-    cmdclass = {"quicktest": SimpleTestRunner}
-    cmdclass.update(versioneer.get_cmdclass())
-    return cmdclass
+    return versioneer.get_cmdclass()
 
 
-major_version = versioneer.get_version().split("+")[0]
-setup(name='lbmpy',
-      version=versioneer.get_version(),
-      description='Code Generation for Lattice Boltzmann Methods',
-      long_description=readme(),
-      long_description_content_type="text/markdown",
-      author='Martin Bauer, Markus Holzer, Frederik Hennig',
-      license='AGPLv3',
-      author_email='cs10-codegen@fau.de',
-      url='https://i10git.cs.fau.de/pycodegen/lbmpy/',
-      packages=['lbmpy'] + ['lbmpy.' + s for s in find_packages('lbmpy')],
-      install_requires=[f'pystencils>=0.4.0,<={major_version}', 'sympy>=1.5.1,<=1.10.1', 'numpy>=1.11.0'],
-      package_data={'lbmpy': ['phasefield/simplex_projection.pyx', 'phasefield/simplex_projection.c']},
-      ext_modules=cython_extensions("lbmpy.phasefield.simplex_projection"),
-      classifiers=[
-          'Development Status :: 4 - Beta',
-          'Framework :: Jupyter',
-          'Topic :: Software Development :: Code Generators',
-          'Topic :: Scientific/Engineering :: Physics',
-          'Intended Audience :: Developers',
-          'Intended Audience :: Science/Research',
-          'License :: OSI Approved :: GNU Affero General Public License v3 or later (AGPLv3+)',
-      ],
-      python_requires=">=3.8",
-      extras_require={
-          'gpu': ['pycuda'],
-          'opencl': ['pyopencl'],
-          'alltrafos': ['islpy', 'py-cpuinfo'],
-          'interactive': ['scipy', 'scikit-image', 'cython', 'matplotlib',
-                          'ipy_table', 'imageio', 'jupyter', 'pyevtk'],
-          'doc': ['sphinx', 'sphinx_rtd_theme', 'nbsphinx',
-                  'sphinxcontrib-bibtex', 'sphinx_autodoc_typehints', 'pandoc'],
-          'phasefield': ['Cython']
-      },
-      cmdclass=get_cmdclass()
-      )
+setup(
+    version=versioneer.get_version(),
+    cmdclass=get_cmdclass(),
+)

src/lbmpy/__init__.py

+from .creationfunctions import (
+    create_lb_ast,
+    create_lb_collision_rule,
+    create_lb_function,
+    create_lb_method,
+    create_lb_update_rule,
+    LBMConfig,
+    LBMOptimisation,
+)
+from .enums import Stencil, Method, ForceModel, CollisionSpace, SubgridScaleModel
+from .lbstep import LatticeBoltzmannStep
+from .macroscopic_value_kernels import (
+    pdf_initialization_assignments,
+    macroscopic_values_getter,
+    strain_rate_tensor_getter,
+    compile_macroscopic_values_getter,
+    compile_macroscopic_values_setter,
+    create_advanced_velocity_setter_collision_rule,
+)
+from .maxwellian_equilibrium import get_weights
+from .relaxationrates import (
+    relaxation_rate_from_lattice_viscosity,
+    lattice_viscosity_from_relaxation_rate,
+    relaxation_rate_from_magic_number,
+)
+from .scenarios import create_lid_driven_cavity, create_fully_periodic_flow
+from .stencils import LBStencil
+
+
+__all__ = [
+    "create_lb_ast",
+    "create_lb_collision_rule",
+    "create_lb_function",
+    "create_lb_method",
+    "create_lb_update_rule",
+    "LBMConfig",
+    "LBMOptimisation",
+    "Stencil",
+    "Method",
+    "ForceModel",
+    "CollisionSpace",
+    "SubgridScaleModel",
+    "LatticeBoltzmannStep",
+    "pdf_initialization_assignments",
+    "macroscopic_values_getter",
+    "strain_rate_tensor_getter",
+    "compile_macroscopic_values_getter",
+    "compile_macroscopic_values_setter",
+    "create_advanced_velocity_setter_collision_rule",
+    "get_weights",
+    "relaxation_rate_from_lattice_viscosity",
+    "lattice_viscosity_from_relaxation_rate",
+    "relaxation_rate_from_magic_number",
+    "create_lid_driven_cavity",
+    "create_fully_periodic_flow",
+    "LBStencil",
+]
+
+
+from . import _version
+__version__ = _version.get_versions()['version']

src/lbmpy/_compat.py

+from pystencils import __version__ as ps_version
+
+#   Determine if we're running pystencils 1.x or 2.x
+version_tokes = ps_version.split(".")
+
+PYSTENCILS_VERSION_MAJOR = int(version_tokes[0])
+IS_PYSTENCILS_2 = PYSTENCILS_VERSION_MAJOR == 2
+
+if IS_PYSTENCILS_2:
+    from pystencils.defaults import DEFAULTS
+
+    def get_loop_counter_symbol(coord: int):
+        return DEFAULTS.spatial_counters[coord]
+
+    def get_supported_instruction_sets():
+        from pystencils import Target
+        vector_targets = Target.available_vector_cpu_targets()
+        isas = []
+        for target in vector_targets:
+            tokens = target.name.split("_")
+            isas.append(tokens[-1].lower())
+        return isas
+
+else:
+    from pystencils.backends.simd_instruction_sets import (
+        get_supported_instruction_sets as get_supported_instruction_sets_,
+    )
+
+    get_supported_instruction_sets = get_supported_instruction_sets_
+
+    def get_loop_counter_symbol(coord: int):
+        from pystencils.astnodes import LoopOverCoordinate
+
+        return LoopOverCoordinate.get_loop_counter_symbol(coord)
+
+
+def import_guard_pystencils1(feature):
+    if IS_PYSTENCILS_2:
+        raise ImportError(
+            f"The following feature is not yet available when running pystencils 2.x: {feature}"
+        )
+    return True

lbmpy/advanced_streaming/__init__.py → src/lbmpy/advanced_streaming/__init__.py

-from .indexing import BetweenTimestepsIndexing, NeighbourOffsetArrays
+from .indexing import BetweenTimestepsIndexing
 from .communication import get_communication_slices, LBMPeriodicityHandling
 from .utility import Timestep, get_accessor, is_inplace, get_timesteps, \
     numeric_index, numeric_offsets, inverse_dir_index, AccessPdfValues
 
-__all__ = ['BetweenTimestepsIndexing', 'NeighbourOffsetArrays',
+__all__ = ['BetweenTimestepsIndexing',
            'get_communication_slices', 'LBMPeriodicityHandling',
            'Timestep', 'get_accessor', 'is_inplace', 'get_timesteps',
            'numeric_index', 'numeric_offsets', 'inverse_dir_index', 'AccessPdfValues']

lbmpy/advanced_streaming/indexing.py → src/lbmpy/advanced_streaming/indexing.py

@@ -2,18 +2,20 @@ import numpy as np
 import sympy as sp
 import pystencils as ps
 
-from pystencils.typing import TypedSymbol, create_type
-from pystencils.backends.cbackend import CustomCodeNode
+from .._compat import IS_PYSTENCILS_2
 
-from lbmpy.advanced_streaming.utility import get_accessor, inverse_dir_index, is_inplace, Timestep
+if IS_PYSTENCILS_2:
+    from pystencils import TypedSymbol, create_type
+    from pystencils.types.quick import Arr
+    from lbmpy.lookup_tables import TranslationArraysNode
+else:
+    from pystencils.typing import TypedSymbol, create_type
+    from ..custom_code_nodes import TranslationArraysNode
 
+from lbmpy.advanced_streaming.utility import get_accessor, inverse_dir_index, is_inplace, Timestep
 from itertools import product
 
 
-def _array_pattern(dtype, name, content):
-    return f"const {str(dtype)} {name} [] = {{ {','.join(str(c) for c in content)} }}; \n"
-
-
 class BetweenTimestepsIndexing:
 
     #   ==============================================
@@ -30,7 +32,7 @@ class BetweenTimestepsIndexing:
 
     @property
     def inverse_dir_symbol(self):
-        """Symbol denoting the inversion of a PDF field index. 
+        """Symbol denoting the inversion of a PDF field index.
         Use only at top-level of index to f_out or f_in, otherwise it can't be correctly replaced."""
         return sp.IndexedBase('invdir')
 
@@ -69,13 +71,21 @@ class BetweenTimestepsIndexing:
         assert f_dir in ['in', 'out']
         inv = '_inv' if inverse else ''
         name = f"f_{f_dir}{inv}_dir_idx"
-        return TypedSymbol(name, self._index_dtype)
+        if IS_PYSTENCILS_2:
+            return TypedSymbol(name, Arr(self._index_dtype, self._q))
+        else:
+            return TypedSymbol(name, self._index_dtype)
 
     def _offset_array_symbols(self, f_dir, inverse):
         assert f_dir in ['in', 'out']
         inv = '_inv' if inverse else ''
         name_base = f"f_{f_dir}{inv}_offsets_"
-        symbols = [TypedSymbol(name_base + d, self._index_dtype) for d in self._coordinate_names]
+
+        if IS_PYSTENCILS_2:
+            symbols = [TypedSymbol(name_base + d, Arr(self._index_dtype, self._q)) for d in self._coordinate_names]
+        else:
+            symbols = [TypedSymbol(name_base + d, self._index_dtype) for d in self._coordinate_names]
+        
         return symbols
 
     def _array_symbols(self, f_dir, inverse, index):
@@ -168,90 +178,31 @@ class BetweenTimestepsIndexing:
         return trivial_index_translations, trivial_offset_translations
 
     def create_code_node(self):
-        return BetweenTimestepsIndexing.TranslationArraysNode(self)
-
-    class TranslationArraysNode(CustomCodeNode):
-
-        def __init__(self, indexing):
-            code = ''
-            symbols_defined = set()
-
-            for f_dir, inv in indexing._required_index_arrays:
-                indices, offsets = indexing._get_translated_indices_and_offsets(f_dir, inv)
-                index_array_symbol = indexing._index_array_symbol(f_dir, inv)
-                symbols_defined.add(index_array_symbol)
-                code += _array_pattern(indexing._index_dtype, index_array_symbol.name, indices)
-
-            for f_dir, inv in indexing._required_offset_arrays:
-                indices, offsets = indexing._get_translated_indices_and_offsets(f_dir, inv)
-                offset_array_symbols = indexing._offset_array_symbols(f_dir, inv)
-                symbols_defined |= set(offset_array_symbols)
-                for d, arrsymb in enumerate(offset_array_symbols):
-                    code += _array_pattern(indexing._offsets_dtype, arrsymb.name, offsets[d])
-
-            super(BetweenTimestepsIndexing.TranslationArraysNode, self).__init__(
-                code, symbols_read=set(), symbols_defined=symbols_defined)
-
-        def __str__(self):
-            return "Variable PDF Access Translation Arrays"
-
-        def __repr__(self):
-            return "Variable PDF Access Translation Arrays"
-
-#   end class AdvancedStreamingIndexing
-
+        array_content = list()
+        symbols_defined = set()
+        for f_dir, inv in self._required_index_arrays:
+            indices, offsets = self._get_translated_indices_and_offsets(f_dir, inv)
+            index_array_symbol = self._index_array_symbol(f_dir, inv)
+            symbols_defined.add(index_array_symbol)
 
-class NeighbourOffsetArrays(CustomCodeNode):
+            if IS_PYSTENCILS_2:
+                array_content.append((index_array_symbol, indices))
+            else:
+                array_content.append((self._index_dtype, index_array_symbol.name, indices))
 
-    @staticmethod
-    def neighbour_offset(dir_idx, stencil):
-        if isinstance(sp.sympify(dir_idx), sp.Integer):
-            return stencil[dir_idx]
+        for f_dir, inv in self._required_offset_arrays:
+            indices, offsets = self._get_translated_indices_and_offsets(f_dir, inv)
+            offset_array_symbols = self._offset_array_symbols(f_dir, inv)
+            symbols_defined |= set(offset_array_symbols)
+            for d, arrsymb in enumerate(offset_array_symbols):
+                if IS_PYSTENCILS_2:
+                    array_content.append((arrsymb, offsets[d]))
+                else:
+                    array_content.append((self._offsets_dtype, arrsymb.name, offsets[d]))
+
+        if IS_PYSTENCILS_2:
+            return TranslationArraysNode(array_content)
         else:
-            return tuple([sp.IndexedBase(symbol, shape=(1,))[dir_idx]
-                         for symbol in NeighbourOffsetArrays._offset_symbols(len(stencil[0]))])
-
-    @staticmethod
-    def _offset_symbols(dim):
-        return [TypedSymbol(f"neighbour_offset_{d}", create_type(np.int32)) for d in ['x', 'y', 'z'][:dim]]
-
-    def __init__(self, stencil, offsets_dtype=np.int32):
-        offsets_dtype = create_type(offsets_dtype)
-        dim = len(stencil[0])
-
-        array_symbols = NeighbourOffsetArrays._offset_symbols(dim)
-        code = "\n"
-        for i, arrsymb in enumerate(array_symbols):
-            code += _array_pattern(offsets_dtype, arrsymb.name, (d[i] for d in stencil))
-
-        offset_symbols = NeighbourOffsetArrays._offset_symbols(dim)
-        super(NeighbourOffsetArrays, self).__init__(code, symbols_read=set(),
-                                                    symbols_defined=set(offset_symbols))
+            return TranslationArraysNode(array_content, symbols_defined)
 
-
-class MirroredStencilDirections(CustomCodeNode):
-
-    @staticmethod
-    def mirror_stencil(direction, mirror_axis):
-        assert mirror_axis <= len(direction), f"only {len(direction)} axis available for mirage"
-        direction = list(direction)
-        direction[mirror_axis] = -direction[mirror_axis]
-
-        return tuple(direction)
-
-    @staticmethod
-    def _mirrored_symbol(mirror_axis):
-        axis = ['x', 'y', 'z']
-        return TypedSymbol(f"{axis[mirror_axis]}_axis_mirrored_stencil_dir", create_type(np.int32))
-
-    def __init__(self, stencil, mirror_axis, dtype=np.int32):
-        offsets_dtype = create_type(dtype)
-
-        mirrored_stencil_symbol = MirroredStencilDirections._mirrored_symbol(mirror_axis)
-        mirrored_directions = [stencil.index(MirroredStencilDirections.mirror_stencil(direction, mirror_axis))
-                               for direction in stencil]
-        code = "\n"
-        code += _array_pattern(offsets_dtype, mirrored_stencil_symbol.name, mirrored_directions)
-
-        super(MirroredStencilDirections, self).__init__(code, symbols_read=set(),
-                                                        symbols_defined={mirrored_stencil_symbol})
+#   end class AdvancedStreamingIndexing

lbmpy/advanced_streaming/utility.py → src/lbmpy/advanced_streaming/utility.py

@@ -58,24 +58,27 @@ odd_accessors = {
 }
 
 
+def is_inplace(streaming_pattern):
+    if streaming_pattern not in streaming_patterns:
+        raise ValueError('Invalid streaming pattern', streaming_pattern)
+
+    return streaming_pattern in ['aa', 'esotwist', 'esopull', 'esopush']
+
+
 def get_accessor(streaming_pattern: str, timestep: Timestep) -> PdfFieldAccessor:
     if streaming_pattern not in streaming_patterns:
         raise ValueError(
             "Invalid value of parameter 'streaming_pattern'.", streaming_pattern)
 
+    if is_inplace(streaming_pattern) and (timestep == Timestep.BOTH):
+        raise ValueError(f"Invalid timestep for streaming pattern {streaming_pattern}: {str(timestep)}")
+
     if timestep == Timestep.EVEN:
         return even_accessors[streaming_pattern]
     else:
         return odd_accessors[streaming_pattern]
 
 
-def is_inplace(streaming_pattern):
-    if streaming_pattern not in streaming_patterns:
-        raise ValueError('Invalid streaming pattern', streaming_pattern)
-
-    return streaming_pattern in ['aa', 'esotwist', 'esopull', 'esopush']
-
-
 def get_timesteps(streaming_pattern):
     return (Timestep.EVEN, Timestep.ODD) if is_inplace(streaming_pattern) else (Timestep.BOTH, )
 

src/lbmpy/analytical_solutions.py

+from typing import Union
+from numpy.typing import NDArray
+
+
+def poiseuille_flow(middle_distance: Union[float, NDArray], height,
+                    ext_force_density: float, dyn_visc: float) -> Union[float, NDArray]:
+    """
+    Analytical solution for plane Poiseuille flow.
+
+    Args:
+        middle_distance: Distance to the middle plane of the channel.
+        height: Distance between the boundaries.
+        ext_force_density: Force density on the fluid normal to the boundaries.
+        dyn_visc: dyn_visc
+
+    Returns:
+        A numpy array of the poiseuille profile if middle_distance is given as array otherwise of velocity of
+        the position given with middle_distance
+    """
+    return ext_force_density * 1. / (2 * dyn_visc) * (height**2.0 / 4.0 - middle_distance**2.0)