@staticmethod
def max_run(_b, _x):
    """Determine the length of the maximum run of b's in vector x.

        Parameters
        ----------
        b: int
            Integer for counting.

        x: array
            Vector of integers.

        Returns
        -------
        max: int
            Length of maximum run of b's.
        """
    _max = 0
    run = 0
    for i in _x:
        if i == _b:
            run += 1
        else:
            if run > _max:
                _max = run
            run = 0
    if _x[-1] == _b and run > _max:
        _max = run
    return _max
