remove cases of deprecation logic from Builder ahead of v3 (#1766)

Author: slayoo

PySDM/builder.py

@@ -3,7 +3,6 @@
 """
 
 import inspect
-import warnings
 
 import numpy as np
 
@@ -17,13 +16,6 @@
 from PySDM.physics.particle_shape_and_density import LiquidSpheres, MixedPhaseSpheres
 
 
-def _warn_env_as_ctor_arg():
-    warnings.warn(
-        "PySDM > v2.31 Builder expects environment instance as argument",
-        DeprecationWarning,
-    )
-
-
 class Builder:
     def __init__(self, n_sd, backend, environment=None):
         assert not inspect.isclass(backend)
@@ -33,24 +25,11 @@ def __init__(self, n_sd, backend, environment=None):
         self.req_attr = None
         self.aerosol_radius_threshold = 0
         self.condensation_params = None
-
-        if environment is None:
-            _warn_env_as_ctor_arg()
-        else:
-            self._set_environment(environment)
+        self.particulator.environment = environment.instantiate(builder=self)
 
     def _set_condensation_parameters(self, **kwargs):
         self.condensation_params = kwargs
 
-    def set_environment(self, environment):
-        _warn_env_as_ctor_arg()
-        self._set_environment(environment)
-
-    def _set_environment(self, environment):
-        if self.particulator.environment is not None:
-            raise AssertionError("environment has already been set")
-        self.particulator.environment = environment.instantiate(builder=self)
-
     def add_dynamic(self, dynamic):
         assert self.particulator.environment is not None
         key = inspect.getmro(type(dynamic))[-2].__name__
@@ -94,14 +73,6 @@ def build(
     ):
         assert self.particulator.environment is not None
 
-        if "n" in attributes and "multiplicity" not in attributes:
-            attributes["multiplicity"] = attributes["n"]
-            del attributes["n"]
-            warnings.warn(
-                'renaming attributes["n"] to attributes["multiplicity"]',
-                DeprecationWarning,
-            )
-
         if "volume" in attributes and "water mass" not in attributes:
             assert self.particulator.formulae.particle_shape_and_density.__name__ in (
                 LiquidSpheres.__name__,

examples/PySDM_examples/Arabas_et_al_2025/aida.ipynb

@@ -307,7 +307,7 @@
     "d_dry, conc = spectral_sampling.ConstantMultiplicity(dNdD).sample_deterministic(common['n_sd'])\n",
     "\n",
     "ATTRIBUTES = {\n",
-    "    'n': conc * common['volume'],\n",
+    "    'multiplicity': conc * common['volume'],\n",
     "    'dry volume': common['formulae'].trivia.volume(radius=d_dry / 2)\n",
     "}\n",
     "\n",

examples/PySDM_examples/Arabas_et_al_2025/fig_A2.ipynb

@@ -133,8 +133,11 @@
     "        key = f\"{case['dt']}:{n_sd}:{case['seed']}\"\n",
     "        output[backend_key][key] = {\"unfrozen_fraction\": [], \"dt\": case[\"dt\"], \"N\": case[\"N\"]}\n",
     "\n",
-    "        builder = Builder(n_sd=n_sd, backend=backend_class(formulae=formulae, double_precision=double_precision))\n",
-    "        builder.set_environment(Box(dt=case[\"dt\"], dv=d_v))\n",
+    "        builder = Builder(\n",
+    "            n_sd=n_sd,\n",
+    "            backend=backend_class(formulae=formulae, double_precision=double_precision),\n",
+    "            environment=Box(dt=case[\"dt\"], dv=d_v),\n",
+    "        )\n",
     "        builder.add_dynamic(Freezing(immersion_freezing='time-dependent'))\n",
     "        attributes = {\n",
     "            \"multiplicity\": np.full(n_sd, int(case[\"N\"])),\n",

examples/PySDM_examples/Shima_et_al_2009/tutorial_example.py

@@ -7,11 +7,16 @@
 
 
 def run(settings, observers=()):
-    builder = Builder(n_sd=settings.n_sd, backend=CPU(formulae=settings.formulae))
-    builder.set_environment(Box(dv=settings.dv, dt=settings.dt))
+    builder = Builder(
+        n_sd=settings.n_sd,
+        backend=CPU(formulae=settings.formulae),
+        environment=Box(dv=settings.dv, dt=settings.dt),
+    )
     attributes = {}
     sampling = ConstantMultiplicity(settings.spectrum)
-    attributes["volume"], attributes["n"] = sampling.sample_deterministic(settings.n_sd)
+    attributes["volume"], attributes["multiplicity"] = sampling.sample_deterministic(
+        settings.n_sd
+    )
     coalescence = Coalescence(
         collision_kernel=settings.kernel, adaptive=settings.adaptive
     )

tests/unit_tests/exporters/test_vtk_exporter_parcel.py

@@ -34,7 +34,7 @@ def mock_output():
             },
             "attributes": {
                 "radius": np.random.random((100, 10)),
-                "n": np.random.random((100, 10)),
+                "multiplicity": np.random.random((100, 10)),
             },
         }
         return output