MedianBinWidth.py

# Mantid Repository : https://github.com/mantidproject/mantid
#
# Copyright © 2018 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 +
from mantid.api import AlgorithmFactory, HistogramValidator,\
    MatrixWorkspaceProperty, PythonAlgorithm
from mantid.kernel import Direction
import numpy
import roundinghelper


class MedianBinWidth(PythonAlgorithm):

    _PROP_BIN_WIDTH = 'BinWidth'
    _PROP_INPUT_WS = 'InputWorkspace'

    def category(self):
        '''
        Return algorithm's category.
        '''
        return 'Utility\\Calculation'

    def name(self):
        '''
        Return algorithm's name.
        '''
        return 'MedianBinWidth'

    def summary(self):
        '''
        Return algorithm's summary.
        '''
        return ("Calculates the average of workspace's histograms'"
                " median bin widths.")

    def version(self):
        '''
        Return algorithm's version.
        '''
        return 1

    def PyInit(self):
        '''
        Declares algorithm's properties.
        '''
        self.declareProperty(
            MatrixWorkspaceProperty(name=self._PROP_INPUT_WS,
                                    defaultValue='',
                                    validator=HistogramValidator(),
                                    direction=Direction.Input),
            doc='The workspace containing the input data')
        roundinghelper.declare_rounding_property(self)
        self.declareProperty(self._PROP_BIN_WIDTH,
                             defaultValue=0.0,
                             direction=Direction.Output,
                             doc='The averaged median bin width')

    def PyExec(self):
        '''
        Averages the median bin widths of the input workspace.
        '''
        inputWs = self.getProperty(self._PROP_INPUT_WS).value
        roundingMode = self.getProperty(
            roundinghelper.PROP_NAME_ROUNDING_MODE).value
        xs = inputWs.extractX()
        dxs = numpy.diff(xs)
        medians = numpy.median(dxs, axis=1)
        binWidth = numpy.mean(medians)
        binWidth = roundinghelper.round(binWidth, roundingMode)
        self.setProperty(self._PROP_BIN_WIDTH, numpy.abs(binWidth))


AlgorithmFactory.subscribe(MedianBinWidth)