Add NeXus loading helpers

src/ess/dream/io/geant4.py

@@ -10,10 +10,10 @@
     CalibrationData,
     CalibrationFilename,
     Filename,
+    NeXusDetector,
     NeXusDetectorDimensions,
     NeXusDetectorName,
     RawDetector,
-    RawDetectorData,
     RawSample,
     RawSource,
     ReducibleDetectorData,
@@ -64,16 +64,16 @@ def load_geant4_csv(file_path: Filename[RunType]) -> AllRawDetectors[RunType]:
 
 def extract_geant4_detector(
     detectors: AllRawDetectors[RunType], detector_name: NeXusDetectorName
-) -> RawDetector[RunType]:
+) -> NeXusDetector[RunType]:
     """Extract a single detector from a loaded GEANT4 simulation."""
-    return RawDetector[RunType](detectors["instrument"][detector_name])
+    return NeXusDetector[RunType](detectors["instrument"][detector_name])
 
 
 def extract_geant4_detector_data(
-    detector: RawDetector[RunType],
-) -> RawDetectorData[RunType]:
+    detector: NeXusDetector[RunType],
+) -> RawDetector[RunType]:
     """Extract the histogram or event data from a loaded GEANT4 detector."""
-    return RawDetectorData[RunType](extract_detector_data(detector))
+    return RawDetector[RunType](extract_detector_data(detector))
 
 
 def _load_raw_events(file_path: str) -> sc.DataArray:
@@ -176,7 +176,7 @@ def get_sample_position(raw_sample: RawSample[RunType]) -> SamplePosition[RunTyp
 
 
 def patch_detector_data(
-    detector_data: RawDetectorData[RunType],
+    detector_data: RawDetector[RunType],
     source_position: SourcePosition[RunType],
     sample_position: SamplePosition[RunType],
 ) -> ReducibleDetectorData[RunType]:
@@ -188,7 +188,7 @@ def patch_detector_data(
 
 
 def geant4_detector_dimensions(
-    data: RawDetectorData[SampleRun],
+    data: RawDetector[SampleRun],
 ) -> NeXusDetectorDimensions:
     # For geant4 data, we group by detector identifier, so the data already has
     # logical dimensions, so we simply return the dimensions of the detector.

src/ess/dream/io/nexus.py

@@ -13,21 +13,7 @@
   but it is not possible to reshape the data into all the logical dimensions.
 """
 
-import scipp as sc
-from ess.reduce import nexus
-
-from ess.powder.types import (
-    Filename,
-    LoadedNeXusDetector,
-    NeXusDetectorName,
-    RawDetectorData,
-    RawSample,
-    RawSource,
-    ReducibleDetectorData,
-    RunType,
-    SamplePosition,
-    SourcePosition,
-)
+from ess import powder
 
 DETECTOR_BANK_SIZES = {
     "endcap_backward_detector": {
@@ -51,95 +37,19 @@
         "strip": 256,
         "counter": 2,
     },
-    "high_resolution_detector": {
-        "strip": 32,
-        "other": -1,
-    },
+    "high_resolution_detector": {"strip": 32, "other": -1},
     "sans_detector": lambda x: x.fold(
         dim="detector_number",
-        sizes={
-            "strip": 32,
-            "other": -1,
-        },
+        sizes={"strip": 32, "other": -1},
     ),
 }
 
 
-def load_nexus_sample(file_path: Filename[RunType]) -> RawSample[RunType]:
-    return RawSample[RunType](nexus.load_sample(file_path))
-
-
-def dummy_load_sample(file_path: Filename[RunType]) -> RawSample[RunType]:
-    """
-    In test files there is not always a sample, so we need a dummy.
-    """
-    return RawSample[RunType](
-        sc.DataGroup({'position': sc.vector(value=[0, 0, 0], unit='m')})
-    )
-
-
-def load_nexus_source(file_path: Filename[RunType]) -> RawSource[RunType]:
-    return RawSource[RunType](nexus.load_source(file_path))
-
-
-def load_nexus_detector(
-    file_path: Filename[RunType], detector_name: NeXusDetectorName
-) -> LoadedNeXusDetector[RunType]:
-    out = nexus.load_detector(file_path=file_path, detector_name=detector_name)
-    out.pop("pixel_shape", None)
-    return LoadedNeXusDetector[RunType](out)
-
-
-def get_source_position(
-    raw_source: RawSource[RunType],
-) -> SourcePosition[RunType]:
-    return SourcePosition[RunType](raw_source["position"])
-
-
-def get_sample_position(
-    raw_sample: RawSample[RunType],
-) -> SamplePosition[RunType]:
-    return SamplePosition[RunType](raw_sample["position"])
-
-
-def get_detector_data(
-    detector: LoadedNeXusDetector[RunType],
-    detector_name: NeXusDetectorName,
-) -> RawDetectorData[RunType]:
-    da = nexus.extract_detector_data(detector)
-    if detector_name in DETECTOR_BANK_SIZES:
-        da = da.fold(dim="detector_number", sizes=DETECTOR_BANK_SIZES[detector_name])
-    return RawDetectorData[RunType](da)
-
-
-def patch_detector_data(
-    detector_data: RawDetectorData[RunType],
-    source_position: SourcePosition[RunType],
-    sample_position: SamplePosition[RunType],
-) -> ReducibleDetectorData[RunType]:
-    """
-    Patch a detector data object with source and sample positions.
-    Also adds variances to the event data if they are missing.
-    """
-    out = detector_data.copy(deep=False)
-    if out.bins is not None:
-        content = out.bins.constituents["data"]
-        if content.variances is None:
-            content.variances = content.values
-    out.coords["sample_position"] = sample_position
-    out.coords["source_position"] = source_position
-    return ReducibleDetectorData[RunType](out)
+def dream_detector_bank_sizes() -> powder.types.DetectorBankSizes | None:
+    return powder.types.DetectorBankSizes(DETECTOR_BANK_SIZES)
 
 
-providers = (
-    load_nexus_sample,
-    load_nexus_source,
-    load_nexus_detector,
-    get_source_position,
-    get_sample_position,
-    get_detector_data,
-    patch_detector_data,
-)
+providers = (*powder.nexus.providers, dream_detector_bank_sizes)
 """
-Providers for loading and processing DREAM NeXus data.
+Providers for loading and processing NeXus data.
 """

src/ess/powder/__init__.py

@@ -15,6 +15,7 @@
     smoothing,
 )
 from .masking import with_pixel_mask_filenames
+from . import nexus
 
 try:
     __version__ = importlib.metadata.version(__package__ or __name__)
@@ -39,6 +40,7 @@
     "filtering",
     "grouping",
     "masking",
+    "nexus",
     "providers",
     "smoothing",
     "with_pixel_mask_filenames",