HFIRCalculateGoniometer.py

# Mantid Repository : https://github.com/mantidproject/mantid
#
# Copyright © 2020 ISIS Rutherford Appleton Laboratory UKRI,
#   NScD Oak Ridge National Laboratory, European Spallation Source,
#   Institut Laue - Langevin & CSNS, Institute of High Energy Physics, CAS
# SPDX - License - Identifier: GPL - 3.0 +

import math
from mantid.api import AlgorithmFactory, PythonAlgorithm, IPeaksWorkspaceProperty
from mantid.kernel import Direction, Property, V3D, FloatBoundedValidator, VisibleWhenProperty, PropertyCriterion
from mantid.geometry import Goniometer


class HFIRCalculateGoniometer(PythonAlgorithm):
    def category(self):
        return 'Diffraction\\Reduction'

    def summary(self):
        """
        summary of the algorithm
        :return:
        """
        return "Calculate the goniometer for peak making an assumption for constant wavelength and goniometer rotation axes"

    def name(self):
        return "HFIRCalculateGoniometer"

    def seeAlso(self):
        return ["FindPeaksMD", "PredictPeaks", 'SetGoniometer']

    def PyInit(self):
        self.declareProperty(IPeaksWorkspaceProperty('Workspace', '', direction=Direction.InOut),
                             doc='Peaks Workspace to be modified')
        self.declareProperty("Wavelength", Property.EMPTY_DBL, validator=FloatBoundedValidator(0.0),
                             doc="Wavelength to set the workspace, will be the value set on workspace if not provided.")
        self.declareProperty("OverrideProperty", False,
                             "If False then the value for InnerGoniometer and FlipX will be determiend from the workspace, "
                             "it True then the properties will be used")
        condition = VisibleWhenProperty("OverrideProperty", PropertyCriterion.IsNotDefault)

        self.declareProperty("InnerGoniometer", False,
                             "Whether the goniometer to be calculated is the most inner (phi) or most outer (omega)")
        self.setPropertySettings("InnerGoniometer", condition)
        self.declareProperty("FlipX", False,
                             "Used when calculating goniometer angle if the q_lab x value should be negative, "
                             "hence the detector of the other side (right) of the beam")
        self.setPropertySettings("FlipX", condition)

    def PyExec(self):

        peaks = self.getProperty('Workspace').value

        wavelength = self.getProperty("Wavelength").value
        if wavelength == Property.EMPTY_DBL:
            wavelength = float(peaks.run()['wavelength'].value)

        if self.getProperty("OverrideProperty").value:
            flip_x = self.getProperty("FlipX").value
            inner = self.getProperty("InnerGoniometer").value
        else:
            flip_x = peaks.getInstrument().getName() == "HB3A"

            if peaks.getInstrument().getName() == "HB3A":
                inner = math.isclose(peaks.run().getTimeAveragedStd("omega"), 0.0)
            else:
                inner = False

        starting_goniometer = peaks.run().getGoniometer().getR()

        for n in range(peaks.getNumberPeaks()):
            p = peaks.getPeak(n)
            g = Goniometer()
            g.setR(starting_goniometer)
            g.calcFromQSampleAndWavelength(V3D(*p.getQSampleFrame()), wavelength, flip_x, inner)
            self.log().information("Found goniometer omega={:.2f} chi={:.2f} phi={:.2f} for peak {} with Q_sample {}"
                                   .format(*g.getEulerAngles('YZY'), n, p.getQSampleFrame()))
            p.setWavelength(wavelength)
            p.setGoniometerMatrix(g.getR())


AlgorithmFactory.subscribe(HFIRCalculateGoniometer)