Examples

Using PlotWidget

The following example shows how to use the PlotWidget class to create a simple plot with a curve and a filtering tool. In this example, the plot manager (see PlotManager) is not used, at least not directly: the plot manager is integrated in the PlotWidget class.

import numpy as np
import scipy.ndimage as spi
import scipy.signal as sps
from guidata.configtools import get_icon
from guidata.qthelpers import qt_app_context
from qtpy import QtWidgets as QW

import plotpy.config  # Loading icons  # noqa: F401
from plotpy.builder import make


class FilterTestWidget(QW.QWidget):
    """
    Filter testing widget
    parent: parent widget (QWidget)
    x, y: NumPy arrays
    func: function object (the signal filter to be tested)
    """

    def __init__(self, parent, x, y, func):
        QW.QWidget.__init__(self, parent)
        self.setMinimumSize(320, 200)
        self.x = x
        self.y = y
        self.func = func
        # ---plotpy curve item attribute:
        self.curve_item = None
        # ---

    def setup_widget(self, title):
        # ---Create the plot widget:
        plotwidget = make.widget(self, type="curve")
        self.curve_item = make.curve([], [], color="b")
        plotwidget.plot.add_item(self.curve_item)
        plotwidget.plot.set_antialiasing(True)
        # ---

        button = QW.QPushButton("Test filter: {}".format(title))
        button.clicked.connect(self.process_data)
        vlayout = QW.QVBoxLayout()
        vlayout.addWidget(plotwidget)
        vlayout.addWidget(button)
        self.setLayout(vlayout)

        self.update_curve()

    def process_data(self):
        self.y = self.func(self.y)
        self.update_curve()

    def update_curve(self):
        # ---Update curve
        self.curve_item.set_data(self.x, self.y)
        self.curve_item.plot().replot()
        # ---


class WindowTest(QW.QWidget):
    def __init__(self):
        QW.QWidget.__init__(self)
        self.setWindowTitle("Signal filtering (plotpy)")
        self.setWindowIcon(get_icon("plotpy.svg"))
        hlayout = QW.QHBoxLayout()
        self.setLayout(hlayout)

    def add_plot(self, x, y, func, title):
        widget = FilterTestWidget(self, x, y, func)
        widget.setup_widget(title)
        self.layout().addWidget(widget)


def test_filter1():
    """Testing this simple Qt/plotpy example"""
    x = np.linspace(-10, 10, 500)
    y = np.random.rand(len(x)) + 5 * np.sin(2 * x**2) / x
    with qt_app_context(exec_loop=True):
        win = WindowTest()
        win.add_plot(x, y, lambda x: spi.gaussian_filter1d(x, 1.0), "Gaussian")
        win.add_plot(x, y, sps.wiener, "Wiener")
        win.show()


if __name__ == "__main__":
    test_filter1()

Using a plot manager

Even if this simple example does not justify the use of the PlotManager (this is an unnecessary complication here), it shows how to use it. In more complex applications, using the PlotManager allows to design highly versatile graphical user interfaces.

import numpy as np
import scipy.ndimage as spi
import scipy.signal as sps
from guidata.configtools import get_icon
from guidata.qthelpers import qt_app_context, win32_fix_title_bar_background
from qtpy import QtWidgets as QW

import plotpy.config  # Loading icons # noqa: F401
from plotpy.builder import make
from plotpy.plot import BasePlot, BasePlotOptions
from plotpy.plot.manager import PlotManager


class FilterTestWidget(QW.QWidget):
    """
    Filter testing widget
    parent: parent widget (QWidget)
    x, y: NumPy arrays
    func: function object (the signal filter to be tested)
    """

    def __init__(self, parent, x, y, func):
        QW.QWidget.__init__(self, parent)
        self.setMinimumSize(320, 200)
        self.x = x
        self.y = y
        self.func = func
        # ---plotpy related attributes:
        self.plot = None
        self.curve_item = None
        # ---

    def setup_widget(self, title):
        # ---Create the plot widget:
        self.plot = BasePlot(self, options=BasePlotOptions(type="curve"))
        self.curve_item = make.curve([], [], color="b")
        self.plot.add_item(self.curve_item)
        self.plot.set_antialiasing(True)
        # ---

        button = QW.QPushButton("Test filter: {}".format(title))
        button.clicked.connect(self.process_data)
        vlayout = QW.QVBoxLayout()
        vlayout.addWidget(self.plot)
        vlayout.addWidget(button)
        self.setLayout(vlayout)

        self.update_curve()

    def process_data(self):
        self.y = self.func(self.y)
        self.update_curve()

    def update_curve(self):
        # ---Update curve
        self.curve_item.set_data(self.x, self.y)
        self.plot.replot()
        # ---


class WindowTest(QW.QMainWindow):
    def __init__(self):
        super().__init__()
        win32_fix_title_bar_background(self)
        self.setWindowTitle("Signal filtering 2 (plotpy)")
        self.setWindowIcon(get_icon("plotpy.svg"))

        hlayout = QW.QHBoxLayout()
        central_widget = QW.QWidget(self)
        central_widget.setLayout(hlayout)
        self.setCentralWidget(central_widget)
        # ---plotpy plot manager
        self.manager = PlotManager(self)
        # ---

    def add_plot(self, x, y, func, title):
        widget = FilterTestWidget(self, x, y, func)
        widget.setup_widget(title)
        self.centralWidget().layout().addWidget(widget)
        # ---Register plot to manager
        self.manager.add_plot(widget.plot)
        # ---

    def setup_window(self):
        # ---Add toolbar and register manager tools
        toolbar = self.addToolBar("tools")
        self.manager.add_toolbar(toolbar, id(toolbar))
        self.manager.register_all_curve_tools()
        # ---


def test_filter2():
    """Testing this simple Qt/plotpy example"""
    x = np.linspace(-10, 10, 500)
    y = np.random.rand(len(x)) + 5 * np.sin(2 * x**2) / x
    with qt_app_context(exec_loop=True):
        win = WindowTest()
        win.add_plot(x, y, lambda x: spi.gaussian_filter1d(x, 1.0), "Gaussian")
        win.add_plot(x, y, sps.wiener, "Wiener")
        win.setup_window()
        win.show()


if __name__ == "__main__":
    test_filter2()