XasObjectViewer.py

# coding: utf-8
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#
# Copyright (c) 2016-2017 European Synchrotron Radiation Facility
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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"""Tools to visualize spectra"""


__authors__ = ["H. Payno"]
__license__ = "MIT"
__date__ = "04/07/2019"


from est.core.types import XASObject, Spectrum
from est.core.utils.symbol import MU_CHAR
from silx.gui import qt
from silx.gui.plot import Plot1D
from silx.gui.plot.StackView import StackViewMainWindow
from silx.utils.enum import Enum
from silx.gui.widgets.FrameBrowser import HorizontalSliderWithBrowser
from est.gui import icons
from silx.gui import icons as silx_icons
from silx.gui.colors import Colormap
from typing import Iterable
import numpy
import silx
import logging

_logger = logging.getLogger(__name__)

# median spectrum view
silx_version = silx.version.split(".")
if not (int(silx_version[0]) == 0 and int(silx_version[1]) <= 11):
    silx_plot_has_baseline_feature = True
else:
    silx_plot_has_baseline_feature = False
    _logger.warning(
        "a more recent of silx is required to display " "mean spectrum (0.12)"
    )


class ViewType(Enum):
    map = (0,)
    spectrum = (1,)


class _SpectrumViewAction(qt.QAction):
    def __init__(self, parent=None, iView=0):
        qt.QAction.__init__(self, "spectrum view", parent=parent)
        assert iView in (0, 1)  # for now we can only deal with two plot at max
        # otherwise no more icon color to display
        self._iView = iView
        if iView == 0:
            icon = "item-1dim"
        elif iView == 1:
            icon = "item-1dim-black"
        else:
            # if necessary: add more icons, this is the only limitation
            raise NotImplementedError("Only two spectrum views are maanged")
        spectrum_icon = icons.getQIcon(icon)
        self.setIcon(spectrum_icon)
        self.setCheckable(True)


class _MapViewAction(qt.QAction):
    def __init__(self, parent=None):
        qt.QAction.__init__(self, "map view", parent=parent)
        map_icon = silx_icons.getQIcon("image")
        self.setIcon(map_icon)
        self.setCheckable(True)


class XasObjectViewer(qt.QMainWindow):
    """Viewer dedicated to view a XAS object

    :param QObject parent: Qt parent
    :param list mapKeys: list of str keys to propose for the map display
    :param list spectrumsPlots: list of keys if several spectrum plot should be
                                proposed.
    """

    viewTypeChanged = qt.Signal()
    """emitted when the view type change"""

    def __init__(self, parent=None, mapKeys=None, spectrumPlots=None):
        qt.QMainWindow.__init__(self, parent)
        self.setWindowFlags(qt.Qt.Widget)

        # main stack widget
        self._mainWidget = qt.QWidget(parent=self)
        self._mainWidget.setLayout(qt.QVBoxLayout())
        self.setCentralWidget(self._mainWidget)
        # map view
        self._mapView = MapViewer(parent=self, keys=mapKeys)
        self._mainWidget.layout().addWidget(self._mapView)

        # spectrum view
        self._spectrumViews = []
        if spectrumPlots is not None:
            spectrum_views_ = spectrumPlots
        else:
            spectrum_views_ = ("",)
        for spectrumPlot in range(len(spectrum_views_)):
            spectrumView = SpectrumViewer(parent=self)
            self._mainWidget.layout().addWidget(spectrumView)
            self._spectrumViews.append(spectrumView)
        # add toolbar
        toolbar = qt.QToolBar("")
        toolbar.setIconSize(qt.QSize(32, 32))
        self._spectrumViewActions = []
        self.view_actions = qt.QActionGroup(self)
        for iSpectrumView, tooltip in enumerate(spectrum_views_):
            spectrumViewAction = _SpectrumViewAction(parent=None, iView=iSpectrumView)
            self.view_actions.addAction(spectrumViewAction)
            self._spectrumViewActions.append(spectrumViewAction)
            spectrumViewAction.setToolTip(tooltip)
            toolbar.addAction(spectrumViewAction)
        self._mapViewAction = _MapViewAction()
        toolbar.addAction(self._mapViewAction)
        self.view_actions.addAction(self._mapViewAction)

        self.addToolBar(qt.Qt.LeftToolBarArea, toolbar)
        toolbar.setMovable(False)

        # connect signal / Slot
        self._mapViewAction.triggered.connect(self._updateView)
        for spectrumAction in self._spectrumViewActions:
            spectrumAction.triggered.connect(self._updateView)

        # initialize
        self._spectrumViewActions[0].setChecked(True)
        self._updateView()

    def _updateView(self, *arg, **kwargs):
        index, view_type = self.getViewType()
        self._mapView.setVisible(view_type is ViewType.map)
        for iView, spectrumView in enumerate(self._spectrumViews):
            spectrumView.setVisible(view_type is ViewType.spectrum and iView == index)
        self.viewTypeChanged.emit()

    def getViewType(self):
        if self._mapViewAction.isChecked():
            return None, ViewType.map
        else:
            for spectrumViewAction in self._spectrumViewActions:
                if spectrumViewAction.isChecked():
                    return spectrumViewAction._iView, ViewType.spectrum
        return None, None

    def setXASObj(self, xas_obj):
        self._mapView.clear()

        self._mapView.setXasObject(xas_obj)
        for spectrumView in self._spectrumViews:
            spectrumView.clear()
            spectrumView.setXasObject(xas_obj)


class MapViewer(qt.QWidget):
    """
    Widget to display different map of the spectra
    """

    sigFrameChanged = qt.Signal(int)
    """Signal emitter when the frame number has changed."""

    def __init__(self, parent=None, keys=None):
        """

        :param parent:
        :param keys: volume keys to display for the xasObject (Mu,
        NormalizedMu...)
        """
        assert keys is not None
        self._xasObj = None
        qt.QWidget.__init__(self, parent=parent)
        self.setLayout(qt.QVBoxLayout())
        self._mainWindow = StackViewMainWindow(parent=parent)
        self.layout().addWidget(self._mainWindow)
        self.layout().setContentsMargins(0, 0, 0, 0)
        self.layout().setSpacing(0.0)

        self._mainWindow.setKeepDataAspectRatio(True)
        self._mainWindow.setColormap(Colormap(name="temperature"))

        # define the keys combobox
        self._keyWidget = qt.QWidget(parent=self)
        self._keyWidget.setLayout(qt.QHBoxLayout())
        self._keyComboBox = qt.QComboBox(parent=self._keyWidget)
        for key in keys:
            self._keyComboBox.addItem(key)
        self._keyWidget.layout().addWidget(qt.QLabel("view: "))
        self._keyWidget.layout().addWidget(self._keyComboBox)
        self.keySelectionDocker = qt.QDockWidget(parent=self)
        self.keySelectionDocker.setContentsMargins(0, 0, 0, 0)
        self._keyWidget.layout().setContentsMargins(0, 0, 0, 0)
        self._keyWidget.layout().setSpacing(0.0)
        self.keySelectionDocker.setWidget(self._keyWidget)
        # self._mainWindow.addDockWidget(qt.Qt.TopDockWidgetArea, dockWidget)
        self.keySelectionDocker.setAllowedAreas(qt.Qt.TopDockWidgetArea)
        self.keySelectionDocker.setFeatures(qt.QDockWidget.NoDockWidgetFeatures)

        # expose API
        self.getActiveImage = self._mainWindow.getActiveImage
        self.menuBar = self._mainWindow.menuBar

        # connect signal / slot
        self._keyComboBox.currentTextChanged.connect(self._updateView)
        self._mainWindow.sigFrameChanged.connect(self._shareFrameChangedSignal)

    def clear(self):
        self._mainWindow.clear()

    def getActiveKey(self):
        return self._keyComboBox.currentText()

    def setXasObject(self, xas_obj):
        self._xasObj = xas_obj
        self._updateView()

    def _updateView(self, *args, **kwargs):
        if self._xasObj is None:
            return
        # set the map view
        spectra_volume = self._xasObj.spectra.map_to(
            key=self.getActiveKey(),
        )
        self._mainWindow.setStack(spectra_volume)

    def getPlot(self):
        return self._mainWindow.getPlot()

    def _shareFrameChangedSignal(self, frame):
        self.sigFrameChanged.emit(frame)

    def setPerspectiveVisible(self, b):
        """hide the dimension selection"""
        self._mainWindow.setOptionVisible(b)
        self._mainWindow._browser.setVisible(True)


class _ExtendedSliderWithBrowser(HorizontalSliderWithBrowser):
    def __init__(self, parent=None, name=None):
        HorizontalSliderWithBrowser.__init__(self, parent)
        self.layout().insertWidget(0, qt.QLabel(str(name + ":")))


class _CurveOperation(object):
    def __init__(
        self,
        x,
        y,
        legend,
        yaxis=None,
        linestyle=None,
        symbol=None,
        color=None,
        ylabel=None,
        baseline=None,
        alpha=1.0,
    ):
        self.x = x
        self.y = y
        self.legend = legend
        self.yaxis = yaxis
        self.linestyle = linestyle
        self.symbol = symbol
        self.color = color
        self.ylabel = ylabel
        self.baseline = baseline
        self.alpha = alpha


class _XMarkerOperation(object):
    def __init__(self, x, legend, color="blue"):
        self.x = x
        self.legend = legend
        self.color = color


class _RawDataList(qt.QTableWidget):
    def __init__(self, parent):
        qt.QTableWidget.__init__(self, parent)
        self.clear()

    def setData(self, x: Iterable, y: Iterable):
        if len(x) != len(y):
            raise ValueError("x and y should have the same number of element")
        self.setRowCount(len(x))
        self.setHorizontalHeaderLabels(
            ["X (energy converted to eV)", "Y ({})".format(MU_CHAR)]
        )

        for i_row, (x_value, y_value) in enumerate(zip(x, y)):
            x_item = qt.QTableWidgetItem()
            x_item.setText(str(x_value))
            self.setItem(i_row, 0, x_item)
            y_item = qt.QTableWidgetItem()
            y_item.setText(str(y_value))
            self.setItem(i_row, 1, y_item)
        self.resizeColumnsToContents()

    def clear(self):
        super().clear()
        self.setHorizontalHeaderLabels(
            ["X (energy converted to eV)", "Y ({})".format(MU_CHAR)]
        )
        self.setRowCount(0)
        self.setColumnCount(2)
        self.setSortingEnabled(True)
        self.verticalHeader().hide()


class SpectrumViewer(qt.QMainWindow):
    def __init__(self, parent=None):
        self._curveOperations = []
        """List of callaback to produce plot regarding the XASObject.
        Callback function should return a _curve_operation"""
        qt.QMainWindow.__init__(self, parent)

        self.xas_obj = None

        self._plotWidget = Plot1D(parent=self)
        self._rawDataWidget = _RawDataList(parent=self)

        self._tabWidget = qt.QTabWidget(self)
        self._tabWidget.addTab(self._plotWidget, "plot")
        self._tabWidget.addTab(self._rawDataWidget, "data as text")

        self.setCentralWidget(self._tabWidget)

        # frame browsers
        dockWidget = qt.QDockWidget(self)

        frameBrowsers = qt.QWidget(parent=self)
        frameBrowsers.setLayout(qt.QVBoxLayout())
        frameBrowsers.layout().setContentsMargins(0, 0, 0, 0)

        self._dim1FrameBrowser = _ExtendedSliderWithBrowser(parent=self, name="dim 1")
        frameBrowsers.layout().addWidget(self._dim1FrameBrowser)
        self._dim2FrameBrowser = _ExtendedSliderWithBrowser(parent=self, name="dim 2")
        frameBrowsers.layout().addWidget(self._dim2FrameBrowser)
        dockWidget.setWidget(frameBrowsers)

        self.addDockWidget(qt.Qt.BottomDockWidgetArea, dockWidget)
        dockWidget.setAllowedAreas(qt.Qt.BottomDockWidgetArea)
        dockWidget.setFeatures(qt.QDockWidget.NoDockWidgetFeatures)

        # connect signal / slot
        self._dim1FrameBrowser.valueChanged.connect(self._updateSpectrumDisplayed)
        self._dim2FrameBrowser.valueChanged.connect(self._updateSpectrumDisplayed)

    def addCurveOperation(self, callbacks):
        """register an curve to display from Xasobject keys, and a legend

        :param callbacks: callback to call when displaying a specific curve
        :type: Union[list,tuple,function]
        """
        if isinstance(callbacks, (list, tuple)):
            for callback in callbacks:
                self.addCurveOperation(callback)
        else:
            self._curveOperations.append(callbacks)

    def clearCurveOperations(self):
        """Remove all defined curve operation"""
        self._curveOperations.clear()

    def setXasObject(self, xas_obj):
        self.xas_obj = xas_obj
        if self.xas_obj is None:
            self.clear()
        else:
            assert self.xas_obj.spectra.shape[0] >= 0
            assert self.xas_obj.spectra.shape[1] >= 0
            self._dim1FrameBrowser.setRange(0, self.xas_obj.spectra.shape[0] - 1)
            self._dim2FrameBrowser.setRange(0, self.xas_obj.spectra.shape[1] - 1)
            self._updateSpectrumDisplayed()

    def _updateSpectrumDisplayed(self, *args, **kwargs):
        if self.xas_obj is None:
            return
        dim1_index = self._dim1FrameBrowser.value()
        dim2_index = self._dim2FrameBrowser.value()
        if dim1_index < 0 or dim2_index < 0:
            return

        assert dim1_index >= 0
        assert dim2_index >= 0

        spectrum = self.xas_obj.get_spectrum(dim1_index, dim2_index)
        # update raw data tab
        self._rawDataWidget.setData(x=spectrum.energy, y=spectrum.mu)
        # update plot tab
        for operation in self._curveOperations:
            curves = [operation(spectrum)]
            if silx_plot_has_baseline_feature is True:
                new_curves_op = operation(self.xas_obj, index=dim1_index)
                if new_curves_op is not None:
                    curves += new_curves_op
            for res in curves:
                # result can be None or nan if the processing fails. So in this
                # case we won't display anything
                if res is not None and res.x is not None and res.x is not numpy.nan:
                    if isinstance(res, _CurveOperation):
                        kwargs = {
                            "x": res.x,
                            "y": res.y,
                            "legend": res.legend,
                            "yaxis": res.yaxis,
                            "linestyle": res.linestyle,
                            "symbol": res.symbol,
                            "color": res.color,
                            "ylabel": res.ylabel,
                        }
                        if silx_plot_has_baseline_feature:
                            kwargs["baseline"] = (res.baseline,)

                        curve = self._plotWidget.addCurve(**kwargs)
                        curve = self._plotWidget.getCurve(curve)
                        curve.setAlpha(res.alpha)
                    elif isinstance(res, _XMarkerOperation):
                        self._plotWidget.addXMarker(
                            x=res.x, color=res.color, legend=res.legend
                        )
                    else:
                        raise TypeError(
                            "this type of operation is not " "recognized", type(res)
                        )

    def clear(self):
        self._plotWidget.clear()
        self._dim1FrameBrowser.setMaximum(-1)
        self._dim2FrameBrowser.setMaximum(-1)
        self._rawDataWidget.clear()


COLOR_MEAN = "black"
COLOR_STD = "grey"


def _plot_norm(obj, **kwargs):
    if isinstance(obj, XASObject):
        assert "index" in kwargs
        index_dim1 = kwargs["index"]
        spectra = obj.spectra.map_to("normalized_mu", relative_to="energy")
        spectra = spectra[:, index_dim1, :]
        mean = numpy.mean(spectra, axis=1)
        std = numpy.std(spectra, axis=1)
        return (
            _CurveOperation(
                x=obj.energy, y=mean, color=COLOR_MEAN, legend="mean norm", alpha=0.5
            ),
            _CurveOperation(
                x=obj.energy,
                y=mean + std,
                baseline=mean - std,
                color=COLOR_STD,
                legend="std norm",
                alpha=0.5,
            ),
        )
    elif isinstance(obj, Spectrum):
        if obj.normalized_mu is None:
            _logger.error("norm has not been computed yet")
            return
        assert len(obj.energy) == len(obj.normalized_mu)
        return _CurveOperation(
            x=obj.energy, y=obj.normalized_mu, legend="norm", color="black"
        )


def _plot_norm_area(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "norm_area"):
        _logger.error("norm_area has not been computed yet")
        return
    assert len(obj.energy) == len(obj.norm_area)
    return _CurveOperation(
        x=obj.energy, y=obj.norm_area, legend="norm_area", color="orange"
    )


def _plot_mback_mu(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "mback_mu"):
        _logger.error("mback_mu has not been computed yet")
        return
    return _CurveOperation(
        x=obj.energy, y=obj.mback_mu, legend="mback_mu", color="orange"
    )


def _plot_pre_edge(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if obj.pre_edge is None:
        _logger.error("pre_edge has not been computed yet")
        return
    assert len(obj.energy) == len(obj.pre_edge)
    return _CurveOperation(
        x=obj.energy, y=obj.pre_edge, legend="pre edge", color="green"
    )


def _plot_post_edge(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if obj.post_edge is None:
        _logger.error("post_edge has not been computed yet")
        return
    assert len(obj.energy) == len(obj.post_edge)
    return _CurveOperation(
        x=obj.energy, y=obj.post_edge, legend="post edge", color="black"
    )


def _plot_edge(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "e0"):
        _logger.error("e0 has not been computed yet")
        return
    return _XMarkerOperation(x=obj.e0, legend="edge", color="yellow")


def _plot_raw(obj, **kwargs):
    if isinstance(obj, Spectrum):
        if obj.mu is None:
            _logger.error("mu not existing")
            return
        return _CurveOperation(x=obj.energy, y=obj.mu, legend="mu", color="red")
    elif isinstance(obj, XASObject):
        assert "index" in kwargs
        index_dim1 = kwargs["index"]
        spectra = obj.spectra.map_to("normalized_mu", relative_to="energy")
        spectra = spectra[:, index_dim1, :]
        mean = numpy.mean(spectra, axis=1)
        std = numpy.std(spectra, axis=1)
        return (
            _CurveOperation(
                x=obj.energy, y=mean, color=COLOR_MEAN, legend="mean mu", alpha=0.5
            ),
            _CurveOperation(
                x=obj.energy,
                y=mean + std,
                baseline=mean - std,
                color=COLOR_STD,
                legend="mu std",
                alpha=0.5,
            ),
        )
    else:
        raise ValueError("input type is not manged")


def _plot_fpp(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "fpp"):
        _logger.error("fpp has not been computed yet")
        return
    return _CurveOperation(x=obj.energy, y=obj.fpp, legend="fpp", color="blue")


def _plot_f2(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "f2"):
        _logger.error("f2 has not been computed yet")
        return
    return _CurveOperation(x=obj.energy, y=obj.f2, legend="f2", color="orange")


def _plot_chir_mag(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "r"):
        _logger.error("r not computed, unable to display it")
        return
    if not hasattr(obj, "chir_mag"):
        _logger.error("chir_mag not computed, unable to display it")
        return
    return _CurveOperation(x=obj.r, y=obj.chir_mag, legend="chi k (mag)")


def _plot_chir_re(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "r"):
        _logger.error("r not computed, unable to display it")
        return
    if not hasattr(obj, "chir_re"):
        _logger.error("chir_re not computed, unable to display it")
        return
    return _CurveOperation(x=obj.r, y=obj.chir_re, legend="chi k (real)")


def _plot_chir_imag(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "r"):
        _logger.error("r not computed, unable to display it")
        return
    if not hasattr(obj, "chir_im"):
        _logger.error("chir_im not computed, unable to display it")
        return
    return _CurveOperation(x=obj.r, y=obj.chir_im, legend="chi k (imag)")


def _plot_spectrum(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    return _CurveOperation(
        x=obj.energy, y=obj.mu, legend="spectrum", yaxis=None, color="blue"
    )


def _plot_bkg(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "bkg"):
        _logger.error("missing bkg parameter, unable to compute bkg plot")
        return
    return _CurveOperation(
        x=obj.energy, y=obj.bkg, legend="bkg", yaxis=None, color="red"
    )


def _plot_knots(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    if not hasattr(obj, "autobk_details"):
        _logger.error("missing bkg parameter, unable to compute bkg plot")
        return
    return _CurveOperation(
        x=obj.autobk_details.knots_e,
        y=obj.autobk_details.knots_y,
        legend="knots",
        yaxis=None,
        color="green",
        linestyle="",
        symbol="o",
    )


def _exafs_signal_plot(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    missing_keys = obj.get_missing_keys(("EXAFSKValues", "EXAFSSignal"))
    if len(missing_keys) > 0:
        _logger.error(
            "missing keys:", missing_keys, "unable to compute exafs signal plot"
        )
        return
    k = obj["EXAFSKValues"]
    if "KMin" not in obj:
        obj["KMin"] = k.min()
    if "KMax" not in obj:
        obj["KMax"] = k.max()

    idx = (obj["EXAFSKValues"] >= obj["KMin"]) & (obj["EXAFSKValues"] <= obj["KMax"])
    x = obj["EXAFSKValues"][idx]
    y = obj["EXAFSSignal"][idx]
    return _CurveOperation(x=x, y=y, legend="EXAFSSignal")


def _exafs_postedge_plot(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    missing_keys = obj.get_missing_keys(("EXAFSKValues", "PostEdgeB"))
    if len(missing_keys) > 0:
        _logger.error(
            "missing keys:", missing_keys, "unable to compute exafs postedge plot"
        )
        return
    k = obj["EXAFSKValues"]
    if "KMin" not in obj:
        obj["KMin"] = k.min()
    if "KMax" not in obj:
        obj["KMax"] = k.max()

    idx = (obj["EXAFSKValues"] >= obj["KMin"]) & (obj["EXAFSKValues"] <= obj["KMax"])

    x = obj["EXAFSKValues"][idx]
    y = obj["PostEdgeB"][idx]
    return _CurveOperation(x=x, y=y, legend="PostEdge")


def _exafs_knots_plot(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    missing_keys = obj.get_missing_keys(("KnotsX", "KnotsY"))
    if len(missing_keys) > 0:
        _logger.error(
            "missing keys:", missing_keys, "unable to compute exafs knot plot"
        )
        return
    x = obj["KnotsX"]
    y = obj["KnotsY"]
    return _CurveOperation(x=x, y=y, legend="Knots", linestyle="", symbol="o")


def _normalized_exafs(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    assert isinstance(obj, Spectrum)
    missing_keys = obj.get_missing_keys(("EXAFSKValues", "EXAFSNormalized"))
    if len(missing_keys) > 0:
        _logger.error(
            "missing keys:", missing_keys, "unable to compute normalized EXAFS"
        )
        return None

    if obj["KWeight"]:
        if obj["KWeight"] == 1:
            ylabel = "EXAFS Signal * k"
        else:
            ylabel = "EXAFS Signal * k^%d" % obj["KWeight"]
    else:
        ylabel = "EXAFS Signal"

    idx = (obj["EXAFSKValues"] >= obj["KMin"]) & (obj["EXAFSKValues"] <= obj["KMax"])

    return _CurveOperation(
        x=obj["EXAFSKValues"][idx],
        y=obj["EXAFSNormalized"][idx],
        legend="Normalized EXAFS",
        ylabel=ylabel,
    )


def _ft_window_plot(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    missing_keys = obj.ft.get_missing_keys(("K", "WindowWeight"))
    if len(missing_keys) > 0:
        _logger.error(
            "missing keys:", missing_keys, "unable to compute normalized EXAFS"
        )
        return None

    return _CurveOperation(
        x=obj.ft["K"],
        y=obj.ft["WindowWeight"],
        legend="FT Window",
        yaxis="right",
        color="red",
    )


def _ft_intensity_plot(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    missing_keys = obj.ft.get_missing_keys(("FTRadius", "FTIntensity"))
    if len(missing_keys) > 0:
        _logger.error("missing keys:", missing_keys, "unable to compute spectrum plot")
        return
    return _CurveOperation(
        x=obj.ft["FTRadius"], y=obj.ft["FTIntensity"], legend="FT Intensity"
    )


def _ft_imaginary_plot(obj, **kwargs):
    if not isinstance(obj, Spectrum):
        return None
    missing_keys = obj.ft.get_missing_keys(("FTRadius", "FTImaginary"))
    if len(missing_keys) > 0:
        _logger.error("missing keys:", missing_keys, "unable to compute spectrum plot")
        return
    return _CurveOperation(
        x=obj.ft["FTRadius"],
        y=obj.ft["FTImaginary"],
        legend="FT Imaginary",
        color="red",
    )