def xfrange(start, stop, step=1, maxSize=-1):
"""
Returns a generator that yields the frames from start to stop, inclusive.
In other words it adds or subtracts a frame, as necessary, to return the
stop value as well, if the stepped range would touch that value.
:type start: int
:type stop: int
:type step: int
:param step: Note that the sign will be ignored
:type maxSize: int
:param maxSize: If >= raise a :class:`fileseq.exceptions.MaxSizeException`
if size is exceeded
:rtype: generator
"""
if start <= stop:
stop, step = stop + 1, abs(step)
else:
stop, step = stop - 1, -abs(step)
if maxSize >= 0:
size = lenRange(start, stop, step)
if size > maxSize:
raise exceptions.MaxSizeException(
"Size %d > %s (MAX_FRAME_SIZE)" % (size, maxSize))
# because an xrange is an odd object all its own, we wrap it in a
# generator expression to get a proper Generator
return (f for f in xrange(start, stop, step))
def xfrange(start, stop, step=1, maxSize=-1):
"""
Returns a generator that yields the frames from start to stop, inclusive.
In other words it adds or subtracts a frame, as necessary, to return the
stop value as well, if the stepped range would touch that value.
Args:
start (int):
stop (int):
step (int): Note that the sign will be ignored
maxSize (int):
Returns:
generator:
Raises:
:class:`fileseq.exceptions.MaxSizeException`: if size is exceeded
"""
if not step:
raise ValueError('xfrange() step argument must not be zero')
start, stop, step = normalizeFrames([start, stop, step])
if start <= stop:
step = abs(step)
else:
step = -abs(step)
if isinstance(start, futils.integer_types):
size = (stop - start) // step + 1
else:
size = int((stop - start) / step) + 1
if maxSize >= 0 and size > maxSize:
raise exceptions.MaxSizeException("Size %d > %s (MAX_FRAME_SIZE)" %
(size, maxSize))
# because an xrange is an odd object all its own, we wrap it in a
# generator expression to get a proper Generator
if isinstance(start, futils.integer_types):
offset = step // abs(step)
return (f for f in range(start, stop + offset, step))
else:
return (start + i * step for i in range(size))