Allow missing end-of-compression labels on history points

docs/examples.md

@@ -245,9 +245,10 @@ must be no greater than 10 s, independent of the time-axis origin.
 
 History-driven RCM points require separate `initial_temperature` and
 `initial_pressure` quantities, using the existing temperature/pressure units.
-This additive shape preserves the meaning of `temperature` and `pressure` in
-every existing file: for RCM they still describe the measured compressed state,
-not the state at the beginning of compression. The ideal-gas reactor instead
+Their `temperature` and `pressure` fields are optional stated labels for the
+measured compressed state; when supplied, they retain that meaning rather than
+describing the state at the beginning of compression. Both fields remain
+required for every point without `volume_history`. The ideal-gas reactor instead
 starts at the explicitly supplied initial state and the first history volume.
 A unit-area wall drives the exact forward slope of the linearly interpolated
 volume, with integration boundaries at every history point. After the history

docs/input_reference.md

@@ -130,10 +130,13 @@ t3:
 
     # An unversioned experimental file retains the legacy citation + data[{T, P, phi, idt}]
     # format and nearest-grid comparison under idt_criterion. A version: 1 file instead contains
-    # points with explicit temperature/pressure/IDT units, a normalized list of SMILES mole
+    # points with explicit IDT units, a normalized list of SMILES mole
     # fractions, apparatus ('shock tube' or 'rapid compression machine'), ignition_definition,
     # optional uncertainty, and source {doi, record}. Each point is simulated directly at its
-    # own state. Supported targets: pressure, temperature, OH, OH*, CH, CH*. Supported types:
+    # own state. Temperature and pressure are required unless a point has volume_history, where
+    # initial_temperature and initial_pressure are required and temperature/pressure are optional
+    # stated compressed-state labels. Supported targets: pressure, temperature, OH, OH*, CH, CH*.
+    # Supported types:
     # 'd/dt max', 'max', '1/2 max', 'd/dt max extrapolated'. Missing target species are refused;
     # no ground-state or radical proxy is substituted. A target event that has not resolved by
     # the integration horizon is also refused rather than scored from a truncated trace. See

t3/schema.py

@@ -347,8 +347,8 @@ class ExperimentalIDTPoint(BaseModel):
     History-driven integration ends no later than 10 s after end of compression,
     so its total elapsed duration is bounded by 20 s. History-free points are unchanged.
     """
-    temperature: ExperimentalTemperature
-    pressure: ExperimentalPressure
+    temperature: ExperimentalTemperature | None = None
+    pressure: ExperimentalPressure | None = None
     composition: list[ExperimentalCompositionEntry]
     apparatus: ExperimentalApparatusEnum
     ignition_definition: ExperimentalIgnitionDefinition
@@ -374,6 +374,8 @@ def volume_history_horizon(self) -> float:
     def validate_volume_history_state(self):
         """Keep existing post-compression state fields unchanged for all RCM points."""
         if self.volume_history is None:
+            if self.temperature is None or self.pressure is None:
+                raise ValueError('temperature and pressure are required without a volume_history')
             if self.initial_temperature is not None or self.initial_pressure is not None:
                 raise ValueError('initial_temperature and initial_pressure require a volume_history')
             return self

t3/simulate/cantera_idt.py

@@ -918,8 +918,8 @@ def _compare_versioned_experiment(self, exp: dict) -> dict:
             criterion = raw_point['ignition_definition']
             experimental_idt = convert_time_to_seconds(point.idt.value, point.idt.units)
             comparison = {
-                'temperature': raw_point['temperature'],
-                'pressure': raw_point['pressure'],
+                'temperature': raw_point.get('temperature'),
+                'pressure': raw_point.get('pressure'),
                 'composition': raw_point['composition'],
                 'apparatus': raw_point['apparatus'],
                 'idt_exp': experimental_idt,

tests/test_simulate/test_experimental_idt.py

@@ -86,6 +86,26 @@ def test_rcm_volume_history_schema_accepts_units_and_initial_states():
     assert parsed.temperature.value == 1400.0
 
 
+def test_rcm_volume_history_schema_allows_absent_compressed_state_labels():
+    point = _rcm_history_point()
+    del point['temperature']
+    del point['pressure']
+
+    parsed = _parsed_rcm_point(point)
+
+    assert parsed.temperature is None
+    assert parsed.pressure is None
+
+
+@pytest.mark.parametrize('field', ['temperature', 'pressure'])
+def test_history_free_point_requires_compressed_state_labels(field):
+    point = _point()
+    del point[field]
+
+    with pytest.raises(ValidationError, match='temperature and pressure are required without a volume_history'):
+        ExperimentalIDTFile.model_validate({'version': 1, 'points': [point]})
+
+
 @pytest.mark.parametrize('mutation, message', [
     ({'time': {'values': [0.0], 'units': 's'}, 'volume': {'values': [1.0], 'units': 'm3'}}, 'at least two'),
     ({'time': {'values': [0.0, 1.0], 'units': 's'}}, 'equal length'),
@@ -260,10 +280,26 @@ def test_rcm_volume_history_reactive_ignition_is_relative_to_compression():
     result = adapter._compare_versioned_experiment({'version': 1, 'points': [_rcm_history_point()]})
     assert result['n_matched'] == 1
     assert result['points'][0]['idt_sim'] == pytest.approx(expected, rel=1e-9)
+    assert result['points'][0]['temperature'] == {'value': 1400.0, 'units': 'K'}
+    assert result['points'][0]['pressure'] == {'value': 5.0, 'units': 'bar'}
     assert expected > 0
     assert np.max(history.T) > 2000
 
 
+def test_rcm_volume_history_simulates_without_compressed_state_labels():
+    adapter = _adapter()
+    point = _rcm_history_point()
+    del point['temperature']
+    del point['pressure']
+
+    result = adapter._compare_versioned_experiment({'version': 1, 'points': [point]})
+
+    assert result['n_matched'] == 1
+    assert result['points'][0]['idt_sim'] > 0
+    assert result['points'][0]['temperature'] is None
+    assert result['points'][0]['pressure'] is None
+
+
 def test_rcm_volume_history_ignition_does_not_depend_on_time_origin():
     adapter = _adapter()
     point = _rcm_history_point()