def calculate_bar_width(self):
        """Determines which series has the most data points and then
        calculates a width for bars based on the range for `x` for that
        series. Flot treats the barWidth setting in terms of graph
        units (not pixels)."""
        slices = max([len(s['data']) for s in self._series])
        xs = [pair[0] for pair in chain(*[s['data'] for s in self._series])]
        xmin, xmax = (min(xs), max(xs))
        w = xmax - xmin
        return float(w)/slices
dataset/ETHPy150Open unbracketed/python-flot-utils/pyflot/graph.py/Flot.calculate_bar_width/original