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

.. only:: html

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

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

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

.. _sphx_glr_examples_gallery_plot_annotate_corners.py:

Draw a track map with numbered corners
=========================================

Use the position data of a single lap to draw a track map.
Then annotate the map with corner numbers.

.. GENERATED FROM PYTHON SOURCE LINES 8-10

Import FastF1 and load the data. Use the telemetry from the fastest for the
track map. (You could also use any other lap instead.)

.. GENERATED FROM PYTHON SOURCE LINES 10-26

.. code-block:: Python


    import matplotlib.pyplot as plt
    import numpy as np

    import fastf1


    session = fastf1.get_session(2023, 'Silverstone', 'Q')
    session.load()

    lap = session.laps.pick_fastest()
    pos = lap.get_pos_data()

    circuit_info = session.get_circuit_info()









.. GENERATED FROM PYTHON SOURCE LINES 27-35

Define a helper function for rotating points around the origin of the
coordinate system.

The matrix ``[[cos, sin], [-sin, cos]]`` is called a rotation matrix.

By matrix multiplication of the rotation matrix with a vector [x, y], a new
rotated vector [x_rot, y_rot] is obtained.
(See also: https://en.wikipedia.org/wiki/Rotation_matrix)

.. GENERATED FROM PYTHON SOURCE LINES 35-42

.. code-block:: Python


    def rotate(xy, *, angle):
        rot_mat = np.array([[np.cos(angle), np.sin(angle)],
                            [-np.sin(angle), np.cos(angle)]])
        return np.matmul(xy, rot_mat)









.. GENERATED FROM PYTHON SOURCE LINES 43-46

Get the coordinates of the track map from the telemetry of the lap and
rotate the coordinates using the rotation from ``circuit_info`` so that
the track map is oriented correctly. After that, plot the rotated track map.

.. GENERATED FROM PYTHON SOURCE LINES 46-60

.. code-block:: Python


    # Get an array of shape [n, 2] where n is the number of points and the second
    # axis is x and y.
    track = pos.loc[:, ('X', 'Y')].to_numpy()

    # Convert the rotation angle from degrees to radian.
    track_angle = circuit_info.rotation / 180 * np.pi

    # Rotate and plot the track map.
    rotated_track = rotate(track, angle=track_angle)
    plt.plot(rotated_track[:, 0], rotated_track[:, 1])







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

 .. code-block:: none


    [<matplotlib.lines.Line2D object at 0x7fa9b6e3ba00>]



.. GENERATED FROM PYTHON SOURCE LINES 62-67

Finally, the corner markers are plotted. To plot the numbers next to the
track, an offset vector that points straight up is defined. This offset
vector is then rotated by the angle that is given for each corner marker.
A line and circular bubble are drawn and the corner marker text is printed
inside the bubble.

.. GENERATED FROM PYTHON SOURCE LINES 67-103

.. code-block:: Python


    offset_vector = [500, 0]  # offset length is chosen arbitrarily to 'look good'

    # Iterate over all corners.
    for _, corner in circuit_info.corners.iterrows():
        # Create a string from corner number and letter
        txt = f"{corner['Number']}{corner['Letter']}"

        # Convert the angle from degrees to radian.
        offset_angle = corner['Angle'] / 180 * np.pi

        # Rotate the offset vector so that it points sideways from the track.
        offset_x, offset_y = rotate(offset_vector, angle=offset_angle)

        # Add the offset to the position of the corner
        text_x = corner['X'] + offset_x
        text_y = corner['Y'] + offset_y

        # Rotate the text position equivalently to the rest of the track map
        text_x, text_y = rotate([text_x, text_y], angle=track_angle)

        # Rotate the center of the corner equivalently to the rest of the track map
        track_x, track_y = rotate([corner['X'], corner['Y']], angle=track_angle)

        # Draw a circle next to the track.
        plt.scatter(text_x, text_y, color='grey', s=140)

        # Draw a line from the track to this circle.
        plt.plot([track_x, text_x], [track_y, text_y], color='grey')

        # Finally, print the corner number inside the circle.
        plt.text(text_x, text_y, txt,
                 va='center_baseline', ha='center', size='small', color='white')










.. GENERATED FROM PYTHON SOURCE LINES 105-107

Add a title, remove tick labels to clean up the plot, set equal axis ratio,
so that the track is not distorted and show the plot.

.. GENERATED FROM PYTHON SOURCE LINES 107-113

.. code-block:: Python


    plt.title(session.event['Location'])
    plt.xticks([])
    plt.yticks([])
    plt.axis('equal')
    plt.show()



.. image-sg:: /examples_gallery/images/sphx_glr_plot_annotate_corners_001.png
   :alt: Silverstone
   :srcset: /examples_gallery/images/sphx_glr_plot_annotate_corners_001.png
   :class: sphx-glr-single-img






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

   **Total running time of the script:** (0 minutes 3.268 seconds)


.. _sphx_glr_download_examples_gallery_plot_annotate_corners.py:

.. only:: html

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

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

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

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

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


.. only:: html

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

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