User Function plugins

A User Function plugin can be defined by a class or a function in a python package.

A user function plugin defined by a function is a simple python function with one argument: results which contain a python dictionary of ToolResults.

This function returns a python dictionary with x and y (list) data to plot , title, bottom and left (string) labels color and hvscolor (string) or (int) . For user plots with mutli-curves the python dictionary can contains nrplots (int) , x_%i, y_%i (list) data to plot, color_%i and hvscolor_%i (string) or (int) where %i runs from 1 to nrplots. If y_%i is set to None the previous plot will stay shown. , e.g.

def positive(results):
    """ plot positive function values on the LineCut tool

    :param results: dictionary with tool results
    :type results: :obj:`dict`
    :returns: dictionary with user plot data
    :rtype: :obj:`dict`
    """
    userplot = {}
    if "linecut_1" in results:
        userplot = {"x": results["linecut_1"][0],
                    "y": [max(0.0, yy) for yy in results["linecut_1"][1]]}
    return userplot

A user function plugin defined by a class it should have defined __call__ method with one argument: results.

This __call__ function returns a python dictionary with x and y list data to plot and optionally title, bottom and left string labels.

Moreover, the class constructor has one configuration string argument initialized by an initialization parameter, e.g.

class LineCutFlat(object):

    """Flatten line cut"""

    def __init__(self, configuration=None):
        """ constructor

        :param configuration: JSON list with horizontal gap pixels to add
        :type configuration: :obj:`str`
        """
        #: (:obj:`list` <:obj: `str`>) list of indexes for gap
        self.__index = 1
        try:
            self.__flat = float(configuration)
        except Exception:
            self.__flat = 100000000.
            pass

    def __call__(self, results):
        """ call method

        :param results: dictionary with tool results
        :type results: :obj:`dict`
        :returns: dictionary with user plot data
        :rtype: :obj:`dict`
        """
        userplot = {}
    if "tool" in results and results["tool"] == "linecut":
        try:
            nrplots = int(results["nrlinecuts"])
        except Exception:
            nrplots = 0
        userplot["nrplots"] = nrplots
        userplot["title"] = "Linecuts flatten at '%s'" % (self.__flat)

        for i in range(nrplots):
            xlabel = "x_%s" % (i + 1)
            ylabel = "y_%s" % (i + 1)
            label = "linecut_%s" % (i + 1)
            cllabel = "hsvcolor_%s" % (i + 1)
            if label in results:
                userplot[xlabel] = results[label][0]
                userplot[ylabel] = [min(yy, self.__flat)
                                    for yy in results[label][1]]
                userplot[cllabel] = i/float(nrplots)
        if "unit" in results:
            userplot["bottom"] = results["unit"]
            userplot["left"] = "intensity"
        return userplot

or

import json


class DiffPDF(object):

    """diffpy PDF user function"""

    def __init__(self, configuration=None):
        """ constructor

        :param configuration: JSON list with config file and diff index
        :type configuration: :obj:`str`
        """
        #: (:obj:`list` <:obj: `str`>) list of indexes for gap
        self.__configfile = None

        config = None
        try:
            config = json.loads(configuration)
            try:
                self.__index = int(config[1])
            except Exception:
                self.__index = 1
            self.__configfile = str(config[0])
        except Exception:
            self.__index = 1
            self.__configfile = str(configuration)

        from diffpy.pdfgetx import loadPDFConfig
        self.__cfg = loadPDFConfig(self.__configfile)

    def __call__(self, results):
        """ call method

        :param results: dictionary with tool results
        :type results: :obj:`dict`
        :returns: dictionary with user plot data
        :rtype: :obj:`dict`
        """
        userplot = {}
        from diffpy.pdfgetx import PDFGetter
        self.__pg = PDFGetter(config=self.__cfg)
        label = "diff_%s" % self.__index
        if label in results and self.__configfile:
            qq = results[label][0]
            df = results[label][1]
            data_gr = self.__pg(qq, df)
            x = data_gr[0]
            y = data_gr[1]

            userplot = {
                "x": x, "y": y,
                "title": "DiffPDF: %s with %s" % (label, self.__configfile)
            }
        return userplot

or

import json


class LineCut(object):

    """ LineCut selection"""

    def __init__(self, configuration=None):
        """ constructor

        :param configuration: JSON list with horizontal gap pixels to add
        :type configuration: :obj:`str`
        """
        try:
            #: (:obj: `int`) line cut index
            self.__index = int(json.loads(configuration)[0])
        except Exception:
            self.__index = 1
        try:
            #: (:obj: `int`) buffer length
            self.__buflen = max(int(json.loads(configuration)[1]), 1)
        except Exception:
            self.__buflen = 20

        #: (:obj: `list`) buffer
        self.__buffer = []

    def __call__(self, results):
        """ call method

        :param results: dictionary with tool results
        :type results: :obj:`dict`
        :returns: dictionary with user plot data
        :rtype: :obj:`dict`
        """
        userplot = {}
        label = "linecut_%s" % self.__index
        if label in results:
            if len(self.__buffer) >= self.__buflen:
                self.__buffer.pop(0)
            self.__buffer.append([results[label][0], results[label][1]])
            userplot["nrplots"] = len(self.__buffer)
            for i, xy in enumerate(self.__buffer):
                userplot["x_%s" % (i + 1)] = xy[0]
                userplot["y_%s" % (i + 1)] = xy[1]
                if i != len(self.__buffer) - 1:
                    userplot["color_%s" % (i + 1)] = i/float(self.__buflen)
                else:
                    userplot["color_%s" % (i + 1)] = 'r'

            userplot["title"] = "History of %s" % label
            if "unit" in results:
                userplot["bottom"] = results["unit"]
                userplot["left"] = "intensity"
        return userplot

To configure user functions see User Functions settings.