Returns polar mesh for matplotlib.pyplot.pcolormesh() in Cartesian coordinates

    polar coordinates of data points -> polar mesh for colormesh
    polar coordinates is assumed to be equidistanced in a sense that
    the r_values and theta_values are assumed to be equally-spaced.

def construct_polar_mesh_for_colormesh(r_values, theta_values):
    """
    Returns polar mesh for matplotlib.pyplot.pcolormesh() in Cartesian coordinates

    polar coordinates of data points -> polar mesh for colormesh
    polar coordinates is assumed to be equidistanced in a sense that
    the r_values and theta_values are assumed to be equally-spaced.
    """

    mesh_R, mesh_Theta = augment_polar_mesh_for_colormesh(r_values, theta_values)

    mesh_X = mesh_R * np.cos(mesh_Theta)
    mesh_Y = mesh_R * np.sin(mesh_Theta)

    return mesh_X, mesh_Y