Merge pull request #183 from scipp/bc240-lut

Add BC240 TofLUT for DREAM

Author: SimonHeybrock

src/ess/dream/beamline.py

@@ -8,10 +8,18 @@
 
 
 class InstrumentConfiguration(enum.Enum):
-    """Choose between high-flux and high-resolution configurations."""
+    """
+    Choose between high-flux and high-resolution configurations.
 
-    high_flux = enum.auto()
-    high_resolution = enum.auto()
+    The high_flux setting is the same as the high_flux_BC215. Setting the band chopper
+    phase explicitly should be favored over using the high_flux setting which is kept
+    for backwards compatibility.
+    """
+
+    high_flux_BC215 = 1
+    high_flux = 1  # Legacy alias for high_flux
+    high_flux_BC240 = 2
+    high_resolution = 3
 
 
 def choppers(configuration: InstrumentConfiguration) -> dict[str, DiskChopper]:

src/ess/dream/data.py

@@ -2,6 +2,8 @@
 # Copyright (c) 2023 Scipp contributors (https://github.com/scipp)
 """Data for tests and documentation with DREAM."""
 
+from typing import Literal
+
 _version = "2"
 
 __all__ = ["get_path"]
@@ -27,7 +29,9 @@ def _make_pooch():
             "DREAM_simple_pwd_workflow/Cave_TOF_Monitor_diam_in_can.dat": "md5:ef24f4a4186c628574046e6629e31611",  # noqa: E501
             "DREAM_simple_pwd_workflow/Cave_TOF_Monitor_van_can.dat": "md5:2cdef7ad9912652149b7e687381d2e99",  # noqa: E501
             "DREAM_simple_pwd_workflow/Cave_TOF_Monitor_vana_inc_coh.dat": "md5:701d66792f20eb283a4ce76bae0c8f8f",  # noqa: E501
+            # BC215
             "DREAM-high-flux-tof-lookup-table.h5": "md5:1b95a359fa7b0d8b4277806ece9bf279",  # noqa: E501
+            "DREAM-high-flux-tof-lookup-table-BC240-new0.h5": "md5:2cc9dc802082101933429a2ea3624126",  # noqa: E501
             # Smaller files for unit tests
             "DREAM_simple_pwd_workflow/TEST_data_dream_diamond_vana_container_sample_union.csv.zip": "md5:405df9b5ade9d61ab71fe8d8c19bb51b",  # noqa: E501
             "DREAM_simple_pwd_workflow/TEST_data_dream_vana_container_sample_union.csv.zip": "md5:20186119d1debfb0c2352f9db384cd0a",  # noqa: E501
@@ -267,7 +271,7 @@ def simulated_monitor_empty_can() -> str:
     return get_path("DREAM_simple_pwd_workflow/Cave_TOF_Monitor_van_can.dat")
 
 
-def tof_lookup_table_high_flux() -> str:
+def tof_lookup_table_high_flux(bc: Literal[215, 240] = 215) -> str:
     """Path to a HDF5 file containing a lookup table for high-flux ToF.
 
     The table was created using the ``tof`` package and the chopper settings for the
@@ -278,5 +282,17 @@ def tof_lookup_table_high_flux() -> str:
 
     The notebook that was used to create the table can be found at
     https://github.com/scipp/essdiffraction/blob/main/tools/dream-make-tof-lookup-table.ipynb
+
+    Parameters
+    ----------
+    bc:
+        Band-control chopper (BC) setting. The default is 215, which corresponds to the
+        settings of the choppers in the tutorial data.
     """
-    return get_path("DREAM-high-flux-tof-lookup-table.h5")
+    match bc:
+        case 215:
+            return get_path("DREAM-high-flux-tof-lookup-table.h5")
+        case 240:
+            return get_path("DREAM-high-flux-tof-lookup-table-BC240-new0.h5")
+        case _:
+            raise ValueError(f"Unsupported band-control chopper (BC) value: {bc}")

src/ess/dream/workflow.py

@@ -54,8 +54,10 @@ def _get_lookup_table_filename_from_configuration(
     from .data import tof_lookup_table_high_flux
 
     match configuration:
-        case InstrumentConfiguration.high_flux:
-            out = tof_lookup_table_high_flux()
+        case InstrumentConfiguration.high_flux_BC215:
+            out = tof_lookup_table_high_flux(bc=215)
+        case InstrumentConfiguration.high_flux_BC240:
+            out = tof_lookup_table_high_flux(bc=240)
         case InstrumentConfiguration.high_resolution:
             raise NotImplementedError("High resolution configuration not yet supported")
 

src/ess/powder/correction.py

@@ -135,8 +135,9 @@ def normalize_by_monitor_integrated(
 
     if monitor.coords[dim].min() > lo or monitor.coords[dim].max() < hi:
         raise ValueError(
-            "Cannot normalize by monitor: The wavelength range of the monitor is "
-            "smaller than the range of the detector."
+            f"Cannot normalize by monitor: The wavelength range of the monitor "
+            f"({monitor.coords[dim].min().value} to {monitor.coords[dim].max().value}) "
+            f"is smaller than the range of the detector ({lo.value} to {hi.value})."
         )
     monitor = monitor[dim, lo:hi]
     # Strictly limit `monitor` to the range of `detector`.

tests/powder/correction_test.py

@@ -479,7 +479,7 @@ def test_normalize_by_monitor_integrated_raises_if_monitor_range_too_narrow():
             'wavelength': sc.array(dims=['wavelength'], values=[1.0, 3, 4], unit='Å')
         },
     )
-    with pytest.raises(ValueError, match="wavelength range of the monitor is smaller"):
+    with pytest.raises(ValueError, match="smaller than the range of the detector"):
         normalize_by_monitor_integrated(
             CountsWavelength[SampleRun](detector),
             monitor=WavelengthMonitor[SampleRun, CaveMonitor](monitor),