LokiWorkflow with time-of-flight calculation

docs/user-guide/loki/index.md

@@ -7,5 +7,7 @@ maxdepth: 1
 
 loki-direct-beam
 loki-iofq
+loki-reduction-ess
 workflow-widget-loki
+loki-make-tof-lookup-table
 ```

docs/user-guide/loki/loki-make-tof-lookup-table.ipynb

@@ -0,0 +1,125 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "0",
+   "metadata": {},
+   "source": [
+    "# Create a time-of-flight lookup table for LoKI"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "1",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import scipp as sc\n",
+    "from ess.reduce import time_of_flight\n",
+    "from ess.reduce.nexus.types import AnyRun"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "2",
+   "metadata": {},
+   "source": [
+    "## Setting up the workflow\n",
+    "\n",
+    "Note here that for now, we have no chopper in the beamline.\n",
+    "This should be added in the next iteration."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "3",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "source_position = sc.vector([0, 0, 0], unit='m')\n",
+    "\n",
+    "wf = time_of_flight.TofLookupTableWorkflow()\n",
+    "wf[time_of_flight.DiskChoppers[AnyRun]] = {}\n",
+    "wf[time_of_flight.SourcePosition] = source_position\n",
+    "wf[time_of_flight.NumberOfSimulatedNeutrons] = 200_000  # Increase this number for more reliable results\n",
+    "wf[time_of_flight.SimulationSeed] = 1234\n",
+    "wf[time_of_flight.PulseStride] = 1\n",
+    "wf[time_of_flight.LtotalRange] = sc.scalar(9.0, unit=\"m\"), sc.scalar(35.0, unit=\"m\")\n",
+    "wf[time_of_flight.DistanceResolution] = sc.scalar(0.1, unit=\"m\")\n",
+    "wf[time_of_flight.TimeResolution] = sc.scalar(250.0, unit='us')\n",
+    "wf[time_of_flight.LookupTableRelativeErrorThreshold] = 1.0"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "4",
+   "metadata": {},
+   "source": [
+    "## Compute the table"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "5",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "table = wf.compute(time_of_flight.TimeOfFlightLookupTable)\n",
+    "table"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "6",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "table.plot()"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "7",
+   "metadata": {},
+   "source": [
+    "## Save to file"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "8",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Write to file\n",
+    "table.save_hdf5('loki-tof-lookup-table-no-choppers.h5')"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.12.7"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

docs/user-guide/loki/loki-reduction-ess.ipynb

@@ -0,0 +1,163 @@
+{
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "id": "0",
+   "metadata": {},
+   "source": [
+    "# Loki workflow\n",
+    "\n",
+    "A short experimental notebook to illustrate how to set-up and run the reduction workflow for Loki @ ESS."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "1",
+   "metadata": {
+    "tags": []
+   },
+   "outputs": [],
+   "source": [
+    "import scipp as sc\n",
+    "import ess.loki.data  # noqa: F401\n",
+    "from ess import loki\n",
+    "from ess.sans.types import *"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "2",
+   "metadata": {},
+   "source": [
+    "## Workflow setup"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "3",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "wf = loki.LokiWorkflow()\n",
+    "\n",
+    "# Set detector bank name: in this case there is only one bank\n",
+    "wf[NeXusDetectorName] = \"loki_detector_0\"\n",
+    "\n",
+    "# Wavelength and Q binning parameters\n",
+    "wf[WavelengthBins] = sc.linspace(\"wavelength\", 1.0, 13.0, 201, unit=\"angstrom\")\n",
+    "wf[QBins] = sc.linspace(dim=\"Q\", start=0.01, stop=0.3, num=101, unit=\"1/angstrom\")\n",
+    "\n",
+    "# Other parameters\n",
+    "wf[CorrectForGravity] = True\n",
+    "wf[UncertaintyBroadcastMode] = UncertaintyBroadcastMode.upper_bound\n",
+    "wf[ReturnEvents] = False\n",
+    "wf[BeamCenter] = sc.vector([0.0, 0.0, 0.0], unit=\"m\")\n",
+    "wf[DirectBeam] = None\n",
+    "wf[DetectorMasks] = {}\n",
+    "wf[TimeOfFlightLookupTableFilename] = loki.data.loki_tof_lookup_table_no_choppers()\n",
+    "\n",
+    "# Use a small dummy file for testing.\n",
+    "# TODO: We currently use the same file for all runs; this should be updated\n",
+    "# once we have files from an actual run.\n",
+    "wf[Filename[SampleRun]] = loki.data.loki_coda_file_one_event()\n",
+    "wf[Filename[EmptyBeamRun]] = loki.data.loki_coda_file_one_event()\n",
+    "wf[Filename[TransmissionRun[SampleRun]]] = loki.data.loki_coda_file_one_event()\n",
+    "\n",
+    "# Visualize the workflow\n",
+    "wf.visualize(IntensityQ[SampleRun], graph_attr={'rankdir': 'LR'})"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "4",
+   "metadata": {},
+   "source": [
+    "### Compute $I(Q)$\n",
+    "\n",
+    "We compute the `IntensityQ` for the sample run.\n",
+    "\n",
+    "**Note:** since we are currently using the same file for sample, empty-beam, and transmission runs,\n",
+    "the final results are meaningless (NaNs in all Q bins). However, this should not prevent the workflow\n",
+    "from running."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "5",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "wf.compute(IntensityQ[SampleRun])"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "id": "6",
+   "metadata": {},
+   "source": [
+    "## Map over detector banks\n",
+    "\n",
+    "Loki has 9 detectors banks, and in principle we would want to run the same workflow on all banks\n",
+    "(treating all pixels in the same way).\n",
+    "\n",
+    "To compute a reduced result for all banks, we map the workflow over all bank names:"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "7",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "import pandas as pd\n",
+    "\n",
+    "bank_ids = list(range(9))\n",
+    "bank_names = [f'loki_detector_{i}' for i in bank_ids]\n",
+    "param_table = pd.DataFrame({NeXusDetectorName: bank_names}, index=bank_ids).rename_axis(\n",
+    "    index='bank_id'\n",
+    ")\n",
+    "param_table"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "8",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "mapped = wf.map(param_table)\n",
+    "\n",
+    "results = sciline.compute_mapped(mapped, IntensityQ[SampleRun])\n",
+    "\n",
+    "# Convert to a DataGroup for better notebook visualization\n",
+    "sc.DataGroup({str(k): v for k, v in results.items()})"
+   ]
+  }
+ ],
+ "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
+  "language_info": {
+   "codemirror_mode": {
+    "name": "ipython",
+    "version": 3
+   },
+   "file_extension": ".py",
+   "mimetype": "text/x-python",
+   "name": "python",
+   "nbconvert_exporter": "python",
+   "pygments_lexer": "ipython3",
+   "version": "3.12.7"
+  }
+ },
+ "nbformat": 4,
+ "nbformat_minor": 5
+}

pyproject.toml

@@ -32,7 +32,7 @@ requires-python = ">=3.11"
 dependencies = [
   "dask>=2022.1.0",
   "graphviz>=0.20",
-  "essreduce>=25.11.0",
+  "essreduce>=25.12.1",
   "numpy>=1.26.4",
   "pandas>=2.1.2",
   "plopp>=25.03.0",

requirements/base.in

@@ -4,7 +4,7 @@
 # The following was generated by 'tox -e deps', DO NOT EDIT MANUALLY!
 dask>=2022.1.0
 graphviz>=0.20
-essreduce>=25.11.0
+essreduce>=25.12.1
 numpy>=1.26.4
 pandas>=2.1.2
 plopp>=25.03.0