def get_min_max_x(data, getAbsolute):
    """
    Takes as an argument data which is a dictionary, where the values are of
    the form (plotData, xAxisMax)

    Returns:
        The limits for a unified xAxis depending on the max value for the xAxes
        passed in
    """
    # It is assumed that the maximum value is positive
    maxVal= 0
    for key in data:
        maybeMax = data[key][1] if getAbsolute else len(data[key][0])
        maxVal = maybeMax if maybeMax > maxVal else maxVal
    
    # Left hand limit is always zero
    return (0, maxVal)