def _get_center(c):
    """Compute center of ellipse from implicit function coefficients.

    Parameters
    ----------
    c : array_like
        Coefficients of general quadratic polynomial function for
        conic funs.

    Returns
    -------
    xc : float
        x coordinate of center.
    yc : float
        y coordinate of center.
    """
    A, B, C, D, E, _F = c[:]
    den = B ** 2 - 4 * A * C
    xc = (2 * C * D - B * E) / den
    yc = (2 * A * E - B * D) / den
    return xc, yc
