[essreduce, esssans] Allow int dtypes for frame_time coords and extend Loki LUT range

packages/essreduce/src/ess/reduce/unwrap/to_wavelength.py

@@ -154,7 +154,11 @@ def _compute_wavelength_histogram(
         sc.concat([raw_eto, sc.scalar(0.0, unit=eto_unit), pulse_period], dim=key),
         key=key,
     )
-    rebinned = da.rebin({key: new_bins})
+    # Rebin only handles float64 coords, so we need to convert the coordinate
+    # on-the-fly if necessary.
+    rebinned = da.assign_coords(
+        {key: da.coords[key].to(dtype='float64', copy=False)}
+    ).rebin({key: new_bins})
     etos = rebinned.coords[key]
 
     # Create linear interpolator

packages/essreduce/tests/unwrap/unwrap_test.py

@@ -625,3 +625,44 @@ def test_unwrap_int(
         diff_threshold=0.02,
         rtol=0.2 if wavelength_from == "simulation" else 0.01,
     )
+
+
+@pytest.mark.parametrize("dtype", ["int32", "int64", "float32", "float64"])
+@pytest.mark.parametrize("wavelength_from", ["simulation", "analytical"])
+@pytest.mark.parametrize("detector_or_monitor", ["detector", "monitor"])
+def test_unwrap_histogram_other_coord_dtypes(
+    dtype, wavelength_from, detector_or_monitor, simulation_results_psc_choppers
+) -> None:
+    dist = 62.0
+    dim = "frame_time"
+    wf, ref = _make_workflow_histogram_wavelength_from(
+        wavelength_from=wavelength_from,
+        dim=dim,
+        distance=sc.scalar(dist, unit="m"),
+        choppers=fakes.psc_choppers(),
+        seed=378,
+        error_threshold=np.inf,
+        detector_or_monitor=detector_or_monitor,
+    )
+
+    if wavelength_from == "simulation":
+        wf[unwrap.SimulationResults[SampleRun]] = simulation_results_psc_choppers
+
+    if detector_or_monitor == "detector":
+        da = wf.compute(RawDetector[SampleRun])
+        new = da.assign_coords({dim: da.coords[dim].to(dtype=dtype)})
+        wf[RawDetector[SampleRun]] = new
+        wavs = wf.compute(unwrap.WavelengthDetector[SampleRun])
+    else:
+        da = wf.compute(RawMonitor[SampleRun, Monitor0])
+        new = da.assign_coords({dim: da.coords[dim].to(dtype=dtype)})
+        wf[RawMonitor[SampleRun, Monitor0]] = new
+        wavs = wf.compute(unwrap.WavelengthMonitor[SampleRun, Monitor0])
+
+    _validate_result_histogram_wavelength_from(
+        wavs=wavs,
+        ref=ref,
+        percentile=96,
+        diff_threshold=0.4,
+        rtol=0.2 if wavelength_from == "simulation" else 0.01,
+    )

packages/esssans/docs/user-guide/loki/loki-make-wavelength-lookup-table.ipynb

@@ -46,7 +46,7 @@
     "wf[Position[snx.NXsource, AnyRun]] = source_position\n",
     "wf[unwrap.NumberOfSimulatedNeutrons] = 200_000  # Increase this number for more reliable results\n",
     "wf[unwrap.SimulationSeed] = 1234\n",
-    "wf[unwrap.LtotalRange[AnyRun, snx.NXdetector]] = sc.scalar(9.0, unit=\"m\"), sc.scalar(35.0, unit=\"m\")\n",
+    "wf[unwrap.LtotalRange[AnyRun, snx.NXdetector]] = sc.scalar(5.0, unit=\"m\"), sc.scalar(35.0, unit=\"m\")\n",
     "wf[unwrap.DistanceResolution] = sc.scalar(0.1, unit=\"m\")\n",
     "wf[unwrap.TimeResolution] = sc.scalar(250.0, unit='us')"
    ]
@@ -116,7 +116,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.12.12"
+   "version": "3.12.7"
   }
  },
  "nbformat": 4,

packages/esssans/src/ess/loki/data.py

@@ -59,9 +59,9 @@
         # Small CODA file for testing purposes (data from only 5 pulses)
         'loki-coda-5-pulses.hdf': 'md5:8368779651ccf101612b35ca075d0298',
         # Wavelength lookup table without choppers
-        'loki-wavelength-lookup-table-no-choppers.h5': 'md5:3fb133962af6554a9999a753c1724ed4',  # noqa: E501
+        'loki-wavelength-lookup-table-no-choppers.h5': 'md5:34cc975a00383653cce4b3e2356e0dc7',  # noqa: E501
     },
-    version='2',
+    version='3',
 )
 
 
@@ -178,6 +178,8 @@ def loki_lookup_table_no_choppers() -> Path:
     This table was computed using `Create a wavelength lookup table for LoKI
     <../../user-guide/loki/loki-make-wavelength-lookup-table.ipynb>`_
     with ``NumberOfSimulatedNeutrons = 5_000_000``.
+
+    Ltotal range is 5-35 meters.
     """
     return _registry.get_path("loki-wavelength-lookup-table-no-choppers.h5")
 

packages/esssans/src/ess/loki/workflow.py

@@ -10,6 +10,7 @@
 from ess import sans
 from ess.sans.parameters import typical_outputs
 
+from ess.reduce.unwrap import WavelengthLutMode
 from ess.reduce.workflow import register_workflow
 
 from ..sans.types import (
@@ -73,16 +74,25 @@ def load_direct_beam(filename: DirectBeamFilename) -> DirectBeam:
 
 
 @register_workflow
-def LokiWorkflow() -> sciline.Pipeline:
+def LokiWorkflow(
+    wavelength_from: WavelengthLutMode = "file",
+) -> sciline.Pipeline:
     """
     Workflow with default parameters for Loki.
 
+    Parameters
+    ----------
+    wavelength_from:
+        Mode for creating the wavelength lookup table. Possible values are
+        'analytical', 'simulation', and 'file'. See
+        https://scipp.github.io/ess/reduce/user-guide/unwrap/lut-building-methods.html
+
     Returns
     -------
     :
         Loki workflow as a sciline.Pipeline
     """
-    workflow = sans.SansWorkflow()
+    workflow = sans.SansWorkflow(wavelength_from=wavelength_from)
     for provider in loki_providers:
         workflow.insert(provider)
     for key, param in loki_default_parameters().items():