': Convert value using unit to a float.  If value is a sequence, return
the converted sequence.
= INPUT VARIABLES
- value   The value or list of values that need to be converted.
- unit    The units to use for an axis with Epoch data.
= RETURN VALUE
- Returns the value parameter converted to floats.'

@staticmethod
def convert(value, unit, axis):

    import matplotlib.testing.jpl_units as U
    isNotEpoch = True
    isDuration = False
    if (iterable(value) and (not isinstance(value, six.string_types))):
        if (len(value) == 0):
            return []
        else:
            return [EpochConverter.convert(x, unit, axis) for x in value]
    if isinstance(value, U.Epoch):
        isNotEpoch = False
    elif isinstance(value, U.Duration):
        isDuration = True
    if (isNotEpoch and (not isDuration) and units.ConversionInterface.is_numlike(value)):
        return value
    if (unit == None):
        unit = EpochConverter.default_units(value, axis)
    if isDuration:
        return EpochConverter.duration2float(value)
    else:
        return EpochConverter.epoch2float(value, unit)
