.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "_gallery/selection_tools/linear_selector.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        :ref:`Go to the end <sphx_glr_download__gallery_selection_tools_linear_selector.py>`
        to download the full example code.

.. rst-class:: sphx-glr-example-title

.. _sphx_glr__gallery_selection_tools_linear_selector.py:


Linear Selectors
================

Example showing how to use a `LinearSelector` with lines and line collections.

.. GENERATED FROM PYTHON SOURCE LINES 7-122



.. image-sg:: /_gallery/selection_tools/images/sphx_glr_linear_selector_001.webp
   :alt: linear selector
   :srcset: /_gallery/selection_tools/images/sphx_glr_linear_selector_001.webp
   :class: sphx-glr-single-img


.. rst-class:: sphx-glr-script-out

 .. code-block:: none

    /home/runner/work/fastplotlib/fastplotlib/fastplotlib/graphics/_features/_base.py:18: UserWarning: casting float64 array to float32
      warn(f"casting {array.dtype} array to float32")







|

.. code-block:: Python


    # test_example = false

    import fastplotlib as fpl
    import numpy as np


    # create some data
    xs = np.linspace(0, 10 * np.pi, 100)
    sine = np.column_stack([xs, np.sin(xs)])
    cosine = np.column_stack([xs, np.cos(xs)])

    # a varying sine-cosine quilted pattern
    image_xs, image_ys = np.meshgrid(xs, xs)
    multiplier = np.linspace(0, 10, 100)
    image_data = multiplier * np.sin(image_xs) + multiplier * np.cos(image_ys)

    # create a figure
    figure = fpl.Figure(
        shape=(1, 2),
        size=(700, 560)
    )

    # line of a single sine wave from 0 - 10π
    line = figure[0, 0].add_line(sine, cmap="jet")

    # add a linear selector to the line
    line_selector = line.add_linear_selector()

    line_selector_text = (f"x value: {line_selector.selection / np.pi:.2f}π\n"
                          f"y value: {line.data[0, 1]:.2f}\n"
                          f"index: {line_selector.get_selected_index()}")

    # a label that will change to display line data based on the linear selector
    line_selection_label = figure[0, 0].add_text(
        line_selector_text,
        offset=(0., 1.75, 0.),
        anchor="middle-left",
        font_size=32,
        face_color=line.colors[0],
        outline_color="w",
        outline_thickness=0.1,
    )


    # add an event handler using a decorator, selectors are just like other graphics
    # you can also use the .add_event_handler() method directly instead of a decorator
    # see the line collection example below for a non-decorator example
    @line_selector.add_event_handler("selection")
    def line_selector_changed(ev):
        selection = ev.info["value"]
        index = ev.get_selected_index()

        # set text to display selection data
        line_selection_label.text = \
            (f"x value: {selection / np.pi:.2f}π\n"
             f"y value: {line.data[index, 1]:.2f}\n"
             f"index: {index}")

        # set text color based on line color at selection index
        line_selection_label.face_color = line.colors[index]


    # line stack, sine and cosine wave
    line_stack = figure[0, 1].add_line_stack([sine, cosine], colors=["magenta", "cyan"], separation=1)
    line_stack_selector = line_stack.add_linear_selector()

    line_stack_selector_text = (f"x value: {line_stack_selector.selection / np.pi:.2f}π\n"
                                f"index: {line_selector.get_selected_index()}\n"
                                f"sine y value: {line_stack[0].data[0, 1]:.2f}\n"
                                f"cosine y value: {line_stack[1].data[0, 1]:.2f}\n")

    # a label that will change to display line_stack data based on the linear selector
    line_stack_selector_label = figure[0, 1].add_text(
        line_stack_selector_text,
        offset=(0., 7.0, 0.),
        anchor="middle-left",
        font_size=24,
        face_color="w",
    )


    def line_stack_selector_changed(ev):
        selection = ev.info["value"]

        # a linear selectors one a line collection returns a
        # list of selected indices for each graphic in the collection
        index = ev.get_selected_index()[0]

        # set text to display selection data
        line_stack_selector_label.text = \
            (f"x value: {selection / np.pi:.2f}π\n"
             f"index: {index}\n"
             f"sine y value: {line_stack[0].data[index, 1]:.2f}\n"
             f"cosine y value: {line_stack[1].data[index, 1]:.2f}\n")


    # add an event handler, you can also use a decorator
    line_stack_selector.add_event_handler(line_stack_selector_changed, "selection")

    # some axes and camera zoom settings
    for subplot in [figure[0, 0], figure[0, 1]]:
        subplot.axes.grids.xy.visible = True
        subplot.axes.auto_grid = False
        subplot.axes.grids.xy.major_step = (np.pi, 1)
        subplot.axes.grids.xy.minor_step = (0, 0)


    figure.show(maintain_aspect=False)

    # NOTE: `if __name__ == "__main__"` is NOT how to use fastplotlib interactively
    # please see our docs for using fastplotlib interactively in ipython and jupyter
    if __name__ == "__main__":
        print(__doc__)
        fpl.run()


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** (0 minutes 1.388 seconds)


.. _sphx_glr_download__gallery_selection_tools_linear_selector.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example

    .. container:: sphx-glr-download sphx-glr-download-jupyter

      :download:`Download Jupyter notebook: linear_selector.ipynb <linear_selector.ipynb>`

    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: linear_selector.py <linear_selector.py>`

    .. container:: sphx-glr-download sphx-glr-download-zip

      :download:`Download zipped: linear_selector.zip <linear_selector.zip>`


.. only:: html

 .. rst-class:: sphx-glr-signature

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_