Source code for ClusterShell.RangeSet

#
# Copyright (C) 2012-2016 CEA/DAM
# Copyright (C) 2012-2016 Aurelien Degremont <aurelien.degremont@cea.fr>
# Copyright (C) 2015-2017 Stephane Thiell <sthiell@stanford.edu>
#
# This file is part of ClusterShell.
#
# ClusterShell is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# ClusterShell is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with ClusterShell; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

"""
Cluster range set module.

Instances of RangeSet provide similar operations than the builtin set type,
extended to support cluster ranges-like format and stepping support ("0-8/2").
"""

from functools import reduce
from itertools import product
from operator import mul

# Python 3 compatibility
try:
    basestring
except NameError:
    basestring = str


def _normalized_index_bounds(length, start, stop):
    """Return list.index()-like normalized start/stop bounds."""
    if start < 0:
        start = max(0, length + start)
    if stop is None:
        stop = length
    elif stop < 0:
        stop = max(0, length + stop)
    return start, stop


__all__ = ['RangeSetException',
           'RangeSetParseError',
           'RangeSetPaddingError',
           'RangeSet',
           'RangeSetND',
           'AUTOSTEP_DISABLED']

# Special constant used to force turn off autostep feature.
# Note: +inf is 1E400, but a bug in python 2.4 makes it impossible to be
# pickled, so we use less. Later, we could consider sys.maxint here.
AUTOSTEP_DISABLED = 1E100


class RangeSetException(Exception):
    """Base RangeSet exception class."""

class RangeSetParseError(RangeSetException):
    """Raised when RangeSet parsing cannot be done properly."""
    def __init__(self, part, msg):
        if part:
            msg = "%s : \"%s\"" % (msg, part)
        RangeSetException.__init__(self, msg)
        # faulty subrange; this allows you to target the error
        self.part = part

class RangeSetPaddingError(RangeSetParseError):
    """Raised when a fatal padding incoherence occurs"""
    def __init__(self, part, msg):
        RangeSetParseError.__init__(self, part, "padding mismatch (%s)" % msg)


[docs] class RangeSet(set): """ Mutable set of cluster node indexes featuring a fast range-based API. This class aims to ease the management of potentially large cluster range sets and is used by the :class:`.NodeSet` class. RangeSet basic constructors: >>> rset = RangeSet() # empty RangeSet >>> rset = RangeSet("5,10-42") # contains '5', '10' to '42' >>> rset = RangeSet("0-10/2") # contains '0', '2', '4', '6', '8', '10' >>> rset = RangeSet("00-10/2") # contains '00', '02', '04', '06', '08', '10' Also any iterable of integers can be specified as first argument: >>> RangeSet([3, 6, 8, 7, 1]) 1,3,6-8 >>> rset2 = RangeSet(rset) Padding of ranges (eg. "003-009") is inferred from input arguments and managed automatically. This is new in ClusterShell v1.9, where mixed lengths zero padding is now supported within the same RangeSet. The instance variable `padding` has become a property that can still be used to either get the max padding length in the set, or force a fixed length zero-padding on the set. RangeSet is itself a set and as such, provides an iterator over its items as strings (strings are used since v1.9). It is recommended to use the explicit iterators :meth:`RangeSet.intiter` and :meth:`RangeSet.striter` when iterating over a RangeSet. RangeSet provides methods like :meth:`RangeSet.union`, :meth:`RangeSet.intersection`, :meth:`RangeSet.difference`, :meth:`RangeSet.symmetric_difference` and their in-place versions :meth:`RangeSet.update`, :meth:`RangeSet.intersection_update`, :meth:`RangeSet.difference_update`, :meth:`RangeSet.symmetric_difference_update` which conform to the Python Set API. """ _VERSION = 4 # serial version number
[docs] def __init__(self, pattern=None, autostep=None): """Initialize RangeSet object. :param pattern: optional string pattern :param autostep: optional autostep threshold """ set.__init__(self) if pattern is not None and not isinstance(pattern, basestring): pattern = ",".join("%s" % i for i in pattern) if isinstance(pattern, RangeSet): self._autostep = pattern._autostep else: self._autostep = None self.autostep = autostep #: autostep threshold public instance attribute if isinstance(pattern, basestring): self._parse(pattern)
def _parse(self, pattern): """Parse string of comma-separated x-y/step -like ranges""" # Comma separated ranges for subrange in pattern.split(','): subrange = subrange.strip() # ignore whitespaces if subrange.find('/') < 0: baserange, step = subrange, 1 else: baserange, step = subrange.split('/', 1) try: step = int(step) except ValueError: raise RangeSetParseError(subrange, "cannot convert string to integer") begin_sign = end_sign = 1 # sign "scale factor" if baserange.find('-') < 0: if step != 1: raise RangeSetParseError(subrange, "invalid step usage") begin = end = baserange else: # ignore whitespaces in a range try: begin, end = (n.strip() for n in baserange.split('-')) if not begin: # single negative number "-5" begin = end begin_sign = end_sign = -1 except ValueError: try: # -0-3 _, begin, end = (n.strip() for n in baserange.split('-')) begin_sign = -1 except ValueError: # -8--4 _, begin, _, end = (n.strip() for n in baserange.split('-')) begin_sign = end_sign = -1 # compute padding and return node range info tuple try: pad = endpad = 0 if int(begin) != 0: begins = begin.lstrip("0") if len(begin) - len(begins) > 0: pad = len(begin) start = int(begins) else: if len(begin) > 1: pad = len(begin) start = 0 if int(end) != 0: ends = end.lstrip("0") else: ends = end # explicit padding for begin and end must match if len(end) - len(ends) > 0: endpad = len(end) if (pad > 0 or endpad > 0) and len(begin) != len(end): raise RangeSetParseError(subrange, "padding length mismatch") stop = int(ends) except ValueError: if len(subrange) == 0: msg = "empty range" else: msg = "cannot convert string to integer" raise RangeSetParseError(subrange, msg) # check preconditions if pad > 0 and begin_sign < 0: errmsg = "padding not supported in negative ranges" raise RangeSetParseError(subrange, errmsg) if stop > 1e100 or start * begin_sign > stop * end_sign or step < 1: raise RangeSetParseError(subrange, "invalid values in range") self.add_range(start * begin_sign, stop * end_sign + 1, step, pad)
[docs] @classmethod def fromlist(cls, rnglist, autostep=None): """Class method that returns a new RangeSet with ranges from provided list.""" inst = RangeSet(autostep=autostep) inst.updaten(rnglist) return inst
[docs] @classmethod def fromone(cls, index, pad=0, autostep=None): """ Class method that returns a new RangeSet of one single item or a single range. Accepted input arguments can be: - integer and padding length - slice object and padding length - string (1.9+) with padding automatically detected (pad is ignored) """ inst = RangeSet(autostep=autostep) # support slice object with duck-typing try: inst.add(index, pad) except TypeError: if not index.stop: raise ValueError("Invalid range upper limit (%s)" % index.stop) inst.add_range(index.start or 0, index.stop, index.step or 1, pad) return inst
@property def padding(self): """Get largest padding value of whole set""" result = None for si in self: idx, digitlen = int(si), len(si) # explicitly padded? if digitlen > 1 and si[0] == '0': # result always grows bigger as we iterate over a sorted set # with largest padded values at the end result = digitlen return result @padding.setter def padding(self, value): """Force padding length on the whole set""" if value is None: value = 1 cpyset = set(self) self.clear() for i in cpyset: self.add(int(i), pad=value)
[docs] def get_autostep(self): """Get autostep value (property)""" if self._autostep >= AUTOSTEP_DISABLED: return None else: # +1 as user wants node count but it means real steps here return self._autostep + 1
[docs] def set_autostep(self, val): """Set autostep value (property)""" if val is None: # disabled by default for compat with other cluster tools self._autostep = AUTOSTEP_DISABLED else: # - 1 because user means node count, but we mean real steps # (this operation has no effect on AUTOSTEP_DISABLED value) self._autostep = int(val) - 1
autostep = property(get_autostep, set_autostep)
[docs] def dim(self): """Get the number of dimensions of this RangeSet object. Common method with RangeSetND. Here, it will always return 1 unless the object is empty, in that case it will return 0.""" return int(len(self) > 0)
@staticmethod def _sortkey(elem): """Sort key used to order RangeSet elements (mixed padding support): sort by both string length and index.""" if elem.startswith('-'): return (-len(elem), int(elem)) return (len(elem), elem) def _sorted(self): """Get sorted list from inner set.""" # For mixed padding support, sort by both string length and index return sorted(set.__iter__(self), key=self._sortkey)
[docs] def __iter__(self): """Iterate over each element in RangeSet, currently as integers, with no padding information. To guarantee future compatibility, please use the methods intiter() or striter() instead.""" return iter(self._sorted())
[docs] def striter(self): """Iterate over each element in RangeSet as strings with optional zero-padding.""" return iter(self._sorted())
[docs] def intiter(self): """Iterate over each element in RangeSet as integer. Zero padding info is ignored.""" for e in self._sorted(): yield int(e)
[docs] def contiguous(self): """Object-based iterator over contiguous range sets.""" for sli, pad in self._contiguous_slices(): yield RangeSet.fromone(slice(sli.start, sli.stop, sli.step), pad)
[docs] def __reduce__(self): """Return state information for pickling.""" pattern = str(self) if self else None # RangeSet("") raises by design return self.__class__, (pattern,), \ { 'padding': self.padding, \ '_autostep': self._autostep, \ '_version' : RangeSet._VERSION }
[docs] def __setstate__(self, dic): """called upon unpickling""" self.__dict__.update(dic) if getattr(self, '_version', 0) < RangeSet._VERSION: # unpickle from old version? if getattr(self, '_version', 0) <= 1: # v1 (no object versioning) - CSv1.3 setattr(self, '_ranges', [(slice(start, stop + 1, step), pad) \ for start, stop, step, pad in getattr(self, '_ranges')]) elif hasattr(self, '_ranges'): # v2 - CSv1.4-1.5 self_ranges = getattr(self, '_ranges') if self_ranges and not isinstance(self_ranges[0][0], slice): # workaround for object pickled from Python < 2.5 setattr(self, '_ranges', [(slice(start, stop, step), pad) \ for (start, stop, step), pad in self_ranges]) if hasattr(self, '_ranges'): # convert to v3 for sli, pad in getattr(self, '_ranges'): self.add_range(sli.start, sli.stop, sli.step, pad) delattr(self, '_ranges') delattr(self, '_length') if getattr(self, '_version', 0) == 3: # 1.6 - 1.8 padding = getattr(self, 'padding', 0) # convert integer set to string set cpyset = set(self) self.clear() for i in cpyset: self.add(i, pad=padding) # automatic conversion
def _strslices(self): """Stringify slices list (x-y/step format)""" for sli, pad in self._folded_slices(): if sli.start + 1 == sli.stop: yield "%0*d" % (pad, sli.start) else: assert sli.step >= 0, "Internal error: sli.step < 0" if sli.step == 1: yield "%0*d-%0*d" % (pad, sli.start, pad, sli.stop - 1) else: yield "%0*d-%0*d/%d" % (pad, sli.start, pad, sli.stop - 1, \ sli.step)
[docs] def __str__(self): """Get comma-separated range-based string (x-y/step format).""" return ','.join(self._strslices())
# __repr__ is the same as __str__ as it is a valid expression that # could be used to recreate a RangeSet with the same value __repr__ = __str__ def _slices_padding(self, autostep=AUTOSTEP_DISABLED): """Iterator over (slices, padding). Iterator over RangeSet slices, either a:b:1 slices if autostep is disabled (default), or a:b:step slices if autostep is specified. """ # # Now support mixed lengths zero-padding (v1.9) cur_pad = 0 cur_padded = False cur_start = None cur_step = None last_idx = None for si in self._sorted(): # numerical index and length of digits idx, digitlen = int(si), len(si) # is current digit zero-padded? padded = (digitlen > 1 and si[0] == '0') if cur_start is not None: padding_mismatch = False step_mismatch = False # check conditions to yield # - padding mismatch # - step check (step=1 is just a special case if contiguous) if cur_padded: # currently strictly padded, our next item could be # unpadded but with the same length if digitlen != cur_pad: padding_mismatch = True else: # current not padded, and because the set is sorted, # it should stay that way if padded: padding_mismatch = True if not padding_mismatch: # does current range lead to broken step? if cur_step is not None: # only consider it if step is defined if cur_step != idx - last_idx: step_mismatch = True if padding_mismatch or step_mismatch: if cur_step is not None: # stepped is True when autostep setting does apply stepped = (cur_step == 1) or (last_idx - cur_start >= autostep * cur_step) step = cur_step else: stepped = True step = 1 if stepped: yield slice(cur_start, last_idx + 1, step), cur_pad if cur_padded else 0 cur_start = idx cur_padded = padded cur_pad = digitlen else: if padding_mismatch: stop = last_idx + 1 else: stop = last_idx - step + 1 for j in range(cur_start, stop, step): yield slice(j, j + 1, 1), cur_pad if cur_padded else 0 if padding_mismatch: cur_start = idx cur_padded = padded cur_pad = digitlen else: cur_start = last_idx cur_step = idx - last_idx if step_mismatch else None last_idx = idx continue else: # first index cur_padded = padded cur_pad = digitlen cur_start = idx cur_step = None last_idx = idx continue cur_step = idx - last_idx last_idx = idx if cur_start is not None: if cur_step is not None: # stepped is True when autostep setting does apply stepped = (last_idx - cur_start >= self._autostep * cur_step) else: stepped = True if stepped or cur_step == 1: yield slice(cur_start, last_idx + 1, cur_step), cur_pad if cur_padded else 0 else: for j in range(cur_start, last_idx + 1, cur_step): yield slice(j, j + 1, 1), cur_pad if cur_padded else 0 def _contiguous_slices(self): """Internal iterator over contiguous slices in RangeSet.""" return self._slices_padding() def _folded_slices(self): """Internal generator over ranges organized by step.""" return self._slices_padding(self._autostep)
[docs] def slices(self): """ Iterate over RangeSet ranges as Python slide objects. NOTE: zero-padding info is not provided """ for sli, pad in self._folded_slices(): yield sli
[docs] def __getitem__(self, index): """ Return the element at index or a subrange when a slice is specified. """ if isinstance(index, slice): inst = RangeSet() inst._autostep = self._autostep inst.update(self._sorted()[index]) return inst elif isinstance(index, int): return self._sorted()[index] else: raise TypeError("%s indices must be integers" % self.__class__.__name__)
[docs] def index(self, elem, start=0, stop=None): """ Return the zero-based index of element in the sorted RangeSet. This is the reverse operation of :meth:`RangeSet.__getitem__` and behaves like the ``index()`` method of the ``list`` type. The element may be given as a string (zero-padding is then significant) or as an integer. The optional `start` and `stop` arguments restrict the search to the matching subsequence, and may be negative (counted from the end). :raises ValueError: the element is not present in the RangeSet """ if isinstance(elem, basestring): key = elem else: key = str(elem) # set membership is fast and padding-aware for strings if not set.__contains__(self, key): raise ValueError("%s is not in RangeSet" % (elem,)) # Compute the rank in a single O(n) pass (no full sort) by counting # the elements that come before `elem` in iteration order. tkey = self._sortkey(key) found = sum(1 for idx in set.__iter__(self) if self._sortkey(idx) < tkey) if start != 0 or stop is not None: start, stop = _normalized_index_bounds(len(self), start, stop) if not start <= found < stop: raise ValueError("%s is not in RangeSet" % (elem,)) return found
[docs] def split(self, nbr): """ Split the rangeset into nbr sub-rangesets (at most). Each sub-rangeset will have the same number of elements more or less 1. Current rangeset remains unmodified. Returns an iterator. >>> RangeSet("1-5").split(3) RangeSet("1-2") RangeSet("3-4") RangeSet("foo5") """ assert(nbr > 0) # We put the same number of element in each sub-nodeset. slice_size = len(self) // int(nbr) left = len(self) % nbr begin = 0 for i in range(0, min(nbr, len(self))): length = slice_size + int(i < left) yield self[begin:begin + length] begin += length
[docs] def add_range(self, start, stop, step=1, pad=0): """ Add a range (start, stop, step and padding length) to RangeSet. Like the Python built-in function *range()*, the last element is the largest start + i * step less than stop. """ assert start < stop, "please provide ordered node index ranges" assert step > 0 assert pad >= 0 assert stop - start < 1e9, "range too large" if pad == 0: set.update(self, ("%d" % i for i in range(start, stop, step))) else: set.update(self, ("%0*d" % (pad, i) for i in range(start, stop, step)))
[docs] def copy(self): """Return a shallow copy of a RangeSet.""" cpy = self.__class__() cpy._autostep = self._autostep cpy.update(self) return cpy
__copy__ = copy # For the copy module
[docs] def __eq__(self, other): """ RangeSet equality comparison. """ # Return NotImplemented instead of raising TypeError, to # indicate that the comparison is not implemented with respect # to the other type (the other comparand then gets a chance to # determine the result, then it falls back to object address # comparison). if not isinstance(other, RangeSet): return NotImplemented return len(self) == len(other) and self.issubset(other)
# Standard set operations: union, intersection, both differences. # Each has an operator version (e.g. __or__, invoked with |) and a # method version (e.g. union). # Subtle: Each pair requires distinct code so that the outcome is # correct when the type of other isn't suitable. For example, if # we did "union = __or__" instead, then Set().union(3) would return # NotImplemented instead of raising TypeError (albeit that *why* it # raises TypeError as-is is also a bit subtle).
[docs] def __or__(self, other): """Return the union of two RangeSets as a new RangeSet. (I.e. all elements that are in either set.) """ if not isinstance(other, set): return NotImplemented return self.union(other)
[docs] def union(self, other): """Return the union of two RangeSets as a new RangeSet. (I.e. all elements that are in either set.) """ self_copy = self.copy() self_copy.update(other) return self_copy
[docs] def __and__(self, other): """Return the intersection of two RangeSets as a new RangeSet. (I.e. all elements that are in both sets.) """ if not isinstance(other, set): return NotImplemented return self.intersection(other)
[docs] def intersection(self, other): """Return the intersection of two RangeSets as a new RangeSet. (I.e. all elements that are in both sets.) """ self_copy = self.copy() self_copy.intersection_update(other) return self_copy
[docs] def __xor__(self, other): """Return the symmetric difference of two RangeSets as a new RangeSet. (I.e. all elements that are in exactly one of the sets.) """ if not isinstance(other, set): return NotImplemented return self.symmetric_difference(other)
[docs] def symmetric_difference(self, other): """Return the symmetric difference of two RangeSets as a new RangeSet. (ie. all elements that are in exactly one of the sets.) """ self_copy = self.copy() self_copy.symmetric_difference_update(other) return self_copy
[docs] def __sub__(self, other): """Return the difference of two RangeSets as a new RangeSet. (I.e. all elements that are in this set and not in the other.) """ if not isinstance(other, set): return NotImplemented return self.difference(other)
[docs] def difference(self, other): """Return the difference of two RangeSets as a new RangeSet. (I.e. all elements that are in this set and not in the other.) """ self_copy = self.copy() self_copy.difference_update(other) return self_copy
# Membership test
[docs] def __contains__(self, element): """Report whether an element is a member of a RangeSet. Element can be either another RangeSet object, a string or an integer. Called in response to the expression ``element in self``. """ if isinstance(element, set): return element.issubset(self) return set.__contains__(self, str(element))
# Subset and superset test
[docs] def issubset(self, other): """Report whether another set contains this RangeSet.""" self._binary_sanity_check(other) return set.issubset(self, other)
[docs] def issuperset(self, other): """Report whether this RangeSet contains another set.""" self._binary_sanity_check(other) return set.issuperset(self, other)
# Inequality comparisons using the is-subset relation. __le__ = issubset __ge__ = issuperset
[docs] def __lt__(self, other): self._binary_sanity_check(other) return len(self) < len(other) and self.issubset(other)
[docs] def __gt__(self, other): self._binary_sanity_check(other) return len(self) > len(other) and self.issuperset(other)
# Assorted helpers def _binary_sanity_check(self, other): """Check that the other argument to a binary operation is also a set, raising a TypeError otherwise.""" if not isinstance(other, set): raise TypeError("Binary operation only permitted between sets") # In-place union, intersection, differences. # Subtle: The xyz_update() functions deliberately return None, # as do all mutating operations on built-in container types. # The __xyz__ spellings have to return self, though.
[docs] def __ior__(self, other): """Update a RangeSet with the union of itself and another.""" self._binary_sanity_check(other) set.__ior__(self, other) return self
[docs] def union_update(self, other): """Update a RangeSet with the union of itself and another.""" self.update(other)
[docs] def __iand__(self, other): """Update a RangeSet with the intersection of itself and another.""" self._binary_sanity_check(other) set.__iand__(self, other) return self
[docs] def intersection_update(self, other): """Update a RangeSet with the intersection of itself and another.""" set.intersection_update(self, other)
[docs] def __ixor__(self, other): """Update a RangeSet with the symmetric difference of itself and another.""" self._binary_sanity_check(other) set.symmetric_difference_update(self, other) return self
[docs] def symmetric_difference_update(self, other): """Update a RangeSet with the symmetric difference of itself and another.""" set.symmetric_difference_update(self, other)
[docs] def __isub__(self, other): """Remove all elements of another set from this RangeSet.""" self._binary_sanity_check(other) set.difference_update(self, other) return self
[docs] def difference_update(self, other, strict=False): """Remove all elements of another set from this RangeSet. If strict is True, raise KeyError if an element cannot be removed. (strict is a RangeSet addition)""" if strict and other not in self: raise KeyError(set.difference(other, self).pop()) set.difference_update(self, other)
# Python dict-like mass mutations: update, clear
[docs] def update(self, iterable): """Add all indexes (as strings) from an iterable (such as a list).""" assert not isinstance(iterable, basestring) set.update(self, iterable)
[docs] def updaten(self, rangesets): """ Update a rangeset with the union of itself and several others. """ for rng in rangesets: if isinstance(rng, set): self.update(str(i) for i in rng) # 1.9+: force cast to str else: self.update(RangeSet(rng))
[docs] def clear(self): """Remove all elements from this RangeSet.""" set.clear(self)
# Single-element mutations: add, remove, discard
[docs] def add(self, element, pad=0): """Add an element to a RangeSet. This has no effect if the element is already present. ClusterShell 1.9+ uses strings instead of integers to better manage zero-padded ranges with mixed lengths. This method supports either a string or an integer with padding info. :param element: the element to add (integer or string) :param pad: zero padding length (integer); ignored if element is string """ if isinstance(element, basestring): set.add(self, element) else: set.add(self, "%0*d" % (pad, int(element)))
[docs] def remove(self, element, pad=0): """Remove an element from a RangeSet. ClusterShell 1.9+ uses strings instead of integers to better manage zero-padded ranges with mixed lengths. This method supports either a string or an integer with padding info. :param element: the element to remove (integer or string) :param pad: zero padding length (integer); ignored if element is string :raises KeyError: element is not contained in RangeSet :raises ValueError: element is not castable to integer """ if isinstance(element, basestring): set.remove(self, element) else: set.remove(self, "%0*d" % (pad, int(element)))
[docs] def discard(self, element, pad=0): """Discard an element from a RangeSet if it is a member. If the element is not a member, do nothing. ClusterShell 1.9+ uses strings instead of integers to better manage zero-padded ranges with mixed lengths. This method supports either a string or an integer with padding info. :param element: the element to remove (integer or string) :param pad: zero padding length (integer); ignored if element is string """ try: if isinstance(element, basestring): set.discard(self, element) else: set.discard(self, "%0*d" % (pad, int(element))) except ValueError: pass # ignore other object types
[docs] class RangeSetND(object): """ Build a N-dimensional RangeSet object. .. warning:: You don't usually need to use this class directly, use :class:`.NodeSet` instead that has ND support. Empty constructor:: RangeSetND() Build from a list of list of :class:`RangeSet` objects:: RangeSetND([[rs1, rs2, rs3, ...], ...]) Strings are also supported:: RangeSetND([["0-3", "4-10", ...], ...]) Integers are also supported:: RangeSetND([(0, 4), (0, 5), (1, 4), (1, 5), ...] """
[docs] def __init__(self, args=None, pads=None, autostep=None, copy_rangeset=True): """RangeSetND initializer All parameters are optional. :param args: generic "list of list" input argument (default is None) :param pads: list of 0-padding length (default is to not pad any dimensions) :param autostep: autostep threshold (use range/step notation if more than #autostep items meet the condition) - default is off (None) :param copy_rangeset: (advanced) if set to False, do not copy RangeSet objects from args (transfer ownership), which is faster. In that case, you should not modify these objects afterwards (default is True). """ # RangeSetND are arranged as a list of N-dimensional RangeSet vectors self._veclist = [] # Dirty flag to avoid doing veclist folding too often self._dirty = True # Initialize autostep through property self._autostep = None self.autostep = autostep #: autostep threshold public instance attribute # Hint on whether several dimensions are varying or not self._multivar_hint = False if args is None: return for rgvec in args: if rgvec: if isinstance(rgvec[0], basestring): self._veclist.append([RangeSet(rg, autostep=autostep) \ for rg in rgvec]) elif isinstance(rgvec[0], RangeSet): if copy_rangeset: self._veclist.append([rg.copy() for rg in rgvec]) else: self._veclist.append(rgvec) else: if pads is None: self._veclist.append( \ [RangeSet.fromone(rg, autostep=autostep) \ for rg in rgvec]) else: self._veclist.append( \ [RangeSet.fromone(rg, pad, autostep) \ for rg, pad in zip(rgvec, pads)])
[docs] class precond_fold(object): """Decorator to ease internal folding management"""
[docs] def __call__(self, func): def inner(*args, **kwargs): rgnd, fargs = args[0], args[1:] if rgnd._dirty: rgnd._fold() return func(rgnd, *fargs, **kwargs) # modify the decorator meta-data for pydoc # Note: should be later replaced by @wraps (functools) # as of Python 2.5 inner.__name__ = func.__name__ inner.__doc__ = func.__doc__ inner.__dict__ = func.__dict__ inner.__module__ = func.__module__ return inner
[docs] @precond_fold() def copy(self): """Return a new, mutable shallow copy of a RangeSetND.""" cpy = self.__class__() # Shallow "to the extent possible" says the copy module, so here that # means calling copy() on each sub-RangeSet to keep mutability. cpy._veclist = [[rg.copy() for rg in rgvec] for rgvec in self._veclist] cpy._dirty = self._dirty return cpy
__copy__ = copy # For the copy module
[docs] def __eq__(self, other): """RangeSetND equality comparison.""" # Return NotImplemented instead of raising TypeError, to # indicate that the comparison is not implemented with respect # to the other type (the other comparand then gets a change to # determine the result, then it falls back to object address # comparison). if not isinstance(other, RangeSetND): return NotImplemented return len(self) == len(other) and self.issubset(other)
def __bool__(self): return bool(self._veclist) __nonzero__ = __bool__ # Python 2 compat
[docs] def __len__(self): """Count unique elements in N-dimensional rangeset.""" return sum([reduce(mul, [len(rg) for rg in rgvec]) \ for rgvec in self.veclist])
[docs] @precond_fold() def __str__(self): """String representation of N-dimensional RangeSet.""" result = "" for rgvec in self._veclist: result += "; ".join([str(rg) for rg in rgvec]) result += "\n" return result
@precond_fold() def __iter__(self): return self._iter() def _iter(self): """Iterate through individual items as tuples.""" for vec in self._veclist: for ivec in product(*vec): yield ivec
[docs] @precond_fold() def iter_padding(self): """Iterate through individual items as tuples with padding info. As of v1.9, this method returns the largest padding value of each items, as mixed length padding is allowed.""" for vec in self._veclist: for ivec in product(*vec): yield ivec, [rg.padding for rg in vec]
@precond_fold() def _get_veclist(self): """Get folded veclist""" return self._veclist def _set_veclist(self, val): """Set veclist and set dirty flag for deferred folding.""" self._veclist = val self._dirty = True veclist = property(_get_veclist, _set_veclist)
[docs] def vectors(self): """Get underlying :class:`RangeSet` vectors""" return iter(self.veclist)
[docs] def dim(self): """Get the current number of dimensions of this RangeSetND object. Return 0 when object is empty.""" try: return len(self._veclist[0]) except IndexError: return 0
[docs] def pads(self): """Get a tuple of padding length info for each dimension.""" # return a tuple of max padding length for each axis pad_veclist = ((rg.padding or 0 for rg in vec) for vec in self._veclist) return tuple(max(pads) for pads in zip(*pad_veclist))
[docs] def get_autostep(self): """Get autostep value (property)""" if self._autostep >= AUTOSTEP_DISABLED: return None else: # +1 as user wants node count but _autostep means real steps here return self._autostep + 1
[docs] def set_autostep(self, val): """Set autostep value (property)""" # Must conform to RangeSet.autostep logic if val is None: self._autostep = AUTOSTEP_DISABLED else: # Like in RangeSet.set_autostep(): -1 because user means node count, # but we mean real steps (this operation has no effect on # AUTOSTEP_DISABLED value) self._autostep = int(val) - 1 # Update our RangeSet objects for rgvec in self._veclist: for rg in rgvec: rg._autostep = self._autostep
autostep = property(get_autostep, set_autostep)
[docs] @precond_fold() def __getitem__(self, index): """ Return the element at index or a subrange when a slice is specified. """ if isinstance(index, slice): iveclist = [] for rgvec in self._veclist: iveclist += product(*rgvec) assert(len(iveclist) == len(self)) rnd = RangeSetND(iveclist[index], autostep=self.autostep) return rnd elif isinstance(index, int): # find a tuple of integer (multi-dimensional) at position index if index < 0: length = len(self) if index >= -length: index = length + index else: raise IndexError("%d out of range" % index) length = 0 for rgvec in self._veclist: cnt = reduce(mul, [len(rg) for rg in rgvec]) if length + cnt < index: length += cnt else: for ivec in product(*rgvec): if index == length: return ivec length += 1 raise IndexError("%d out of range" % index) else: raise TypeError("%s indices must be integers" % self.__class__.__name__)
[docs] @precond_fold() def index(self, elem, start=0, stop=None): """ Return the zero-based index of element in this RangeSetND, following iteration order. This is the reverse operation of :meth:`RangeSetND.__getitem__` and behaves like the ``index()`` method of the ``list`` type. The element is a vector (tuple) of indexes, given as integers or strings (zero-padding is then significant). The optional `start` and `stop` arguments restrict the search to the matching subsequence, and may be negative (counted from the end). :raises TypeError: the element is not a vector of indexes :raises ValueError: the element is not present in the RangeSetND """ # a bare string or scalar is not a valid index vector: iterating over # a string would otherwise wrongly split it into per-character indexes # (basestring catches both str and Python 2 unicode strings) if isinstance(elem, basestring) or not hasattr(elem, '__iter__'): raise TypeError("%s.index() argument must be a vector of indexes" % self.__class__.__name__) target = tuple("%s" % e for e in elem) for pos, ivec in enumerate(self._iter()): if ivec == target: if start != 0 or stop is not None: start, stop = _normalized_index_bounds(len(self), start, stop) if not start <= pos < stop: break return pos raise ValueError("%s is not in RangeSetND" % (elem,))
[docs] @precond_fold() def contiguous(self): """Object-based iterator over contiguous range sets.""" veclist = self._veclist try: dim = len(veclist[0]) except IndexError: return for dimidx in range(dim): new_veclist = [] for rgvec in veclist: for rgsli in rgvec[dimidx].contiguous(): rgvec = list(rgvec) rgvec[dimidx] = rgsli new_veclist.append(rgvec) veclist = new_veclist for rgvec in veclist: yield RangeSetND([rgvec])
# Membership test
[docs] @precond_fold() def __contains__(self, element): """Report whether an element is a member of a RangeSetND. Element can be either another RangeSetND object, a string or an integer. Called in response to the expression ``element in self``. """ if isinstance(element, RangeSetND): rgnd_element = element else: rgnd_element = RangeSetND([[str(element)]]) return rgnd_element.issubset(self)
# Subset and superset test
[docs] def issubset(self, other): """Report whether another set contains this RangeSetND.""" self._binary_sanity_check(other) return other.issuperset(self)
[docs] @precond_fold() def issuperset(self, other): """Report whether this RangeSetND contains another RangeSetND.""" self._binary_sanity_check(other) if self.dim() == 1 and other.dim() == 1: return self._veclist[0][0].issuperset(other._veclist[0][0]) if not other._veclist: return True test = other.copy() test.difference_update(self) return not bool(test)
# Inequality comparisons using the is-subset relation. __le__ = issubset __ge__ = issuperset
[docs] def __lt__(self, other): self._binary_sanity_check(other) return len(self) < len(other) and self.issubset(other)
[docs] def __gt__(self, other): self._binary_sanity_check(other) return len(self) > len(other) and self.issuperset(other)
# Assorted helpers def _binary_sanity_check(self, other): """Check that the other argument to a binary operation is also a RangeSetND, raising a TypeError otherwise.""" if not isinstance(other, RangeSetND): msg = "Binary operation only permitted between RangeSetND" raise TypeError(msg) def _sort(self): """N-dimensional sorting.""" def rgveckeyfunc(rgvec): # key used for sorting purposes, based on the following # conditions: # (1) larger vector first (#elements) # (2) larger dim first (#elements) # (3) lower first index first # (4) lower last index first return (-reduce(mul, [len(rg) for rg in rgvec]), \ tuple((-len(rg), rg[0], rg[-1]) for rg in rgvec)) self._veclist.sort(key=rgveckeyfunc)
[docs] @precond_fold() def fold(self): """Explicit folding call. Please note that folding of RangeSetND nD vectors are automatically managed, so you should not have to call this method. It may be still useful in some extreme cases where the RangeSetND is heavily modified.""" pass
def _fold(self): """In-place N-dimensional folding.""" assert self._dirty if len(self._veclist) > 1: self._fold_univariate() or self._fold_multivariate() else: self._dirty = False def _fold_univariate(self): """Univariate nD folding. Return True on success and False when a multivariate folding is required.""" dim = self.dim() vardim = dimdiff = 0 if dim > 1: # We got more than one dimension, see if only one is changing... for i in range(dim): # Are all rangesets on this dimension the same? slist = [vec[i] for vec in self._veclist] if slist.count(slist[0]) != len(slist): dimdiff += 1 if dimdiff > 1: break vardim = i univar = (dim == 1 or dimdiff == 1) if univar: # Eligible for univariate folding (faster!) for vec in self._veclist[1:]: self._veclist[0][vardim].update(vec[vardim]) del self._veclist[1:] self._dirty = False self._multivar_hint = not univar return univar def _fold_multivariate(self): """Multivariate nD folding""" # PHASE 1: expand with respect to uniqueness self._fold_multivariate_expand() # PHASE 2: merge self._fold_multivariate_merge() self._dirty = False def _fold_multivariate_expand(self): """Multivariate nD folding: expand [phase 1]""" self._veclist = [[RangeSet.fromone(i, autostep=self.autostep) for i in tvec] for tvec in set(self._iter())] def _fold_multivariate_merge(self): """Multivariate nD folding: merge [phase 2]""" full = False # try easy O(n) passes first chg = True # new pass (eg. after change on veclist) while chg: chg = False self._sort() # sort veclist before new pass index1, index2 = 0, 1 while (index1 + 1) < len(self._veclist): # use 2 references on iterator to compare items by couples item1 = self._veclist[index1] index2 = index1 + 1 index1 += 1 while index2 < len(self._veclist): item2 = self._veclist[index2] index2 += 1 new_item = [None] * len(item1) nb_diff = 0 # compare 2 rangeset vector, item by item, the idea being # to merge vectors if they differ only by one item for pos, (rg1, rg2) in enumerate(zip(item1, item2)): if rg1 == rg2: new_item[pos] = rg1 elif not rg1 & rg2: # merge on disjoint ranges nb_diff += 1 if nb_diff > 1: break new_item[pos] = rg1 | rg2 # if fully contained, keep the largest one elif (rg1 > rg2 or rg1 < rg2): # and nb_diff == 0: nb_diff += 1 if nb_diff > 1: break new_item[pos] = max(rg1, rg2) # otherwise, compute rangeset intersection and # keep the two disjoint part to be handled # later... else: # intersection but do nothing nb_diff = 2 break # one change has been done: use this new item to compare # with other if nb_diff <= 1: chg = True item1 = self._veclist[index1 - 1] = new_item index2 -= 1 self._veclist.pop(index2) elif not full: # easy pass so break to avoid scanning all # index2; advance with next index1 for now break if not chg and not full: # if no change was done during the last normal pass, we do a # full O(n^2) pass. This pass is done only at the end in the # hope that most vectors have already been merged by easy # O(n) passes. chg = full = True
[docs] def __or__(self, other): """Return the union of two RangeSetNDs as a new RangeSetND. (I.e. all elements that are in either set.) """ if not isinstance(other, RangeSetND): return NotImplemented return self.union(other)
[docs] def union(self, other): """Return the union of two RangeSetNDs as a new RangeSetND. (I.e. all elements that are in either set.) """ rgnd_copy = self.copy() rgnd_copy.update(other) return rgnd_copy
[docs] def update(self, other): """Add all RangeSetND elements to this RangeSetND.""" if isinstance(other, RangeSetND): iterable = other._veclist else: iterable = other for vec in iterable: # copy rangesets and set custom autostep assert isinstance(vec[0], RangeSet) cpyvec = [] for rg in vec: cpyrg = rg.copy() cpyrg.autostep = self.autostep cpyvec.append(cpyrg) self._veclist.append(cpyvec) self._dirty = True if not self._multivar_hint: self._fold_univariate()
union_update = update
[docs] def __ior__(self, other): """Update a RangeSetND with the union of itself and another.""" self._binary_sanity_check(other) self.update(other) return self
[docs] def __isub__(self, other): """Remove all elements of another set from this RangeSetND.""" self._binary_sanity_check(other) self.difference_update(other) return self
[docs] def difference_update(self, other, strict=False): """Remove all elements of another set from this RangeSetND. If strict is True, raise KeyError if an element cannot be removed (strict is a RangeSet addition)""" if strict and not other in self: raise KeyError(other.difference(self)[0]) ergvx = other._veclist # read only rgnd_new = [] index1 = 0 while index1 < len(self._veclist): rgvec1 = self._veclist[index1] procvx1 = [ rgvec1 ] nextvx1 = [] index2 = 0 while index2 < len(ergvx): rgvec2 = ergvx[index2] while len(procvx1) > 0: # refine diff for each resulting vector rgproc1 = procvx1.pop(0) tmpvx = [] for pos, (rg1, rg2) in enumerate(zip(rgproc1, rgvec2)): if rg1 == rg2 or rg1 < rg2: # issubset pass elif rg1 & rg2: # intersect tmpvec = list(rgproc1) tmpvec[pos] = rg1.difference(rg2) tmpvx.append(tmpvec) else: # disjoint tmpvx = [ rgproc1 ] # reset previous work break if tmpvx: nextvx1 += tmpvx if nextvx1: procvx1 = nextvx1 nextvx1 = [] index2 += 1 if procvx1: rgnd_new += procvx1 index1 += 1 self.veclist = rgnd_new
[docs] def __sub__(self, other): """Return the difference of two RangeSetNDs as a new RangeSetND. (I.e. all elements that are in this set and not in the other.) """ if not isinstance(other, RangeSetND): return NotImplemented return self.difference(other)
[docs] def difference(self, other): """ ``s.difference(t)`` returns a new object with elements in s but not in t. """ self_copy = self.copy() self_copy.difference_update(other) return self_copy
[docs] def intersection(self, other): """ ``s.intersection(t)`` returns a new object with elements common to s and t. """ self_copy = self.copy() self_copy.intersection_update(other) return self_copy
[docs] def __and__(self, other): """ Implements the & operator. So ``s & t`` returns a new object with elements common to s and t. """ if not isinstance(other, RangeSetND): return NotImplemented return self.intersection(other)
[docs] def intersection_update(self, other): """ ``s.intersection_update(t)`` returns nodeset s keeping only elements also found in t. """ if other is self: return tmp_rnd = RangeSetND() empty_rset = RangeSet() for rgvec in self._veclist: for ergvec in other._veclist: irgvec = [rg.intersection(erg) \ for rg, erg in zip(rgvec, ergvec)] if not empty_rset in irgvec: tmp_rnd.update([irgvec]) # substitute self.veclist = tmp_rnd.veclist
[docs] def __iand__(self, other): """ Implements the &= operator. So ``s &= t`` returns object s keeping only elements also found in t (Python 2.5+ required). """ self._binary_sanity_check(other) self.intersection_update(other) return self
[docs] def symmetric_difference(self, other): """ ``s.symmetric_difference(t)`` returns the symmetric difference of two objects as a new RangeSetND. (ie. all items that are in exactly one of the RangeSetND.) """ self_copy = self.copy() self_copy.symmetric_difference_update(other) return self_copy
[docs] def __xor__(self, other): """ Implement the ^ operator. So ``s ^ t`` returns a new RangeSetND with nodes that are in exactly one of the RangeSetND. """ if not isinstance(other, RangeSetND): return NotImplemented return self.symmetric_difference(other)
[docs] def symmetric_difference_update(self, other): """ ``s.symmetric_difference_update(t)`` returns RangeSetND s keeping all nodes that are in exactly one of the objects. """ diff2 = other.difference(self) self.difference_update(other) self.update(diff2)
[docs] def __ixor__(self, other): """ Implement the ^= operator. So ``s ^= t`` returns object s after keeping all items that are in exactly one of the RangeSetND (Python 2.5+ required). """ self._binary_sanity_check(other) self.symmetric_difference_update(other) return self