disp : bool, optional
        If True, raise RuntimeError if the algorithm didn't converge.
        Otherwise, the convergence status is recorded in any `RootResults`
        return object.

    Returns
    -------
    root : float
        Root of `f` between `a` and `b`.
    r : `RootResults` (present if ``full_output = True``)
        Object containing information about the convergence. In particular,
        ``r.converged`` is True if the routine converged.

    Notes
    -----
    `f` must be continuous.  f(a) and f(b) must have opposite signs.

    Related functions fall into several classes:

    multivariate local optimizers
      `fmin`, `fmin_powell`, `fmin_cg`, `fmin_bfgs`, `fmin_ncg`
    nonlinear least squares minimizer
      `leastsq`
    constrained multivariate optimizers
      `fmin_l_bfgs_b`, `fmin_tnc`, `fmin_cobyla`
    global optimizers
      `basinhopping`, `brute`, `differential_evolution`
    local scalar minimizers
      `fminbound`, `brent`, `golden`, `bracket`
    N-D root-finding
      `fsolve`
    1-D root-finding
      `brenth`, `ridder`, `bisect`, `newton`
    scalar fixed-point finder
      `fixed_point`

    References
    ----------
    .. [Brent1973]
       Brent, R. P.,
       *Algorithms for Minimization Without Derivatives*.
       Englewood Cliffs, NJ: Prentice-Hall, 1973. Ch. 3-4.

    .. [PressEtal1992]
       Press, W. H.; Flannery, B. P.; Teukolsky, S. A.; and Vetterling, W. T.
       *Numerical Recipes in FORTRAN: The Art of Scientific Computing*, 2nd ed.
       Cambridge, England: Cambridge University Press, pp. 352-355, 1992.
       Section 9.3:  "Van Wijngaarden-Dekker-Brent Method."

    Examples
    --------
    >>> def f(x):
    ...     return (x**2 - 1)

    >>> from scipy import optimize

    >>> root = optimize.brentq(f, -2, 0)
    >>> root
    -1.0

    >>> root = optimize.brentq(f, 0, 2)
    >>> root
    1.0
    r