Trac #29103: get rid of part of itervalues

after #29077

There are much more cases, so only half of them is taken care of.

URL: https://trac.sagemath.org/29103
Reported by: chapoton
Ticket author(s): Frédéric Chapoton
Reviewer(s): Travis Scrimshaw

src/sage/categories/crystals.py

@@ -16,12 +16,11 @@
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 2 of the License, or
 # (at your option) any later version.
-# http://www.gnu.org/licenses/
+# https://www.gnu.org/licenses/
 #*****************************************************************************
 
 from __future__ import print_function
 from builtins import zip
-from six import itervalues
 
 from sage.misc.cachefunc import cached_method
 from sage.misc.abstract_method import abstract_method
@@ -789,7 +788,7 @@ def crystal_morphism(self, on_gens, codomain=None,
  codomain = on_gens[0].parent()
  elif isinstance(on_gens, dict):
  if on_gens:
- codomain = next(itervalues(on_gens)).parent()
+ codomain = next(iter(on_gens.values())).parent()
  else:
  for x in self.module_generators:
  y = on_gens(x)

src/sage/combinat/alternating_sign_matrix.py

@@ -32,7 +32,7 @@
 # ****************************************************************************
 from __future__ import division
 from six.moves import range, zip
-from six import itervalues, add_metaclass
+from six import add_metaclass
 
 import copy
 from sage.misc.classcall_metaclass import ClasscallMetaclass
@@ -1495,7 +1495,7 @@ def _lattice_initializer(self):
  """
  mts, rels = MonotoneTriangles(self._n)._lattice_initializer()
  bij = {t: self.from_monotone_triangle(t) for t in mts}
- return (itervalues(bij), [(bij[a], bij[b]) for (a, b) in rels])
+ return (bij.values(), [(bij[a], bij[b]) for (a, b) in rels])
 
  def cover_relations(self):
  r"""

src/sage/combinat/growth.py

@@ -1402,8 +1402,7 @@ def _process_filling_and_shape(self, filling, shape):
  """
  if isinstance(filling, dict):
  try:
- from six import itervalues
- v = next(itervalues(filling))
+ v = next(iter(filling.values()))
  if isinstance(v, dict):
  # it is a dict of dicts
  F = dict()

src/sage/combinat/permutation.py

@@ -229,15 +229,13 @@
 # it under the terms of the GNU General Public License as published by
 # the Free Software Foundation, either version 2 of the License, or
 # (at your option) any later version.
-# http://www.gnu.org/licenses/
+# https://www.gnu.org/licenses/
 #*****************************************************************************
 from __future__ import print_function, absolute_import
 
 from builtins import zip
 from six.moves import range
 
-from six import itervalues
-
 from sage.structure.parent import Parent
 from sage.structure.unique_representation import UniqueRepresentation
 from sage.categories.infinite_enumerated_sets import InfiniteEnumeratedSets
@@ -248,7 +246,7 @@
 from sage.structure.global_options import GlobalOptions
 from sage.interfaces.all import gap
 from sage.rings.all import ZZ, Integer, PolynomialRing
-from sage.arith.all import factorial
+from sage.arith.all import factorial, multinomial
 from sage.matrix.matrix_space import MatrixSpace
 from sage.combinat.tools import transitive_ideal
 from sage.combinat.composition import Composition
@@ -5507,8 +5505,8 @@ def cardinality(self):
  sage: Permutations(3,4).cardinality()
  0
  """
- if self._k <= self.n and self._k >= 0:
- return factorial(self.n) // factorial(self.n-self._k)
+ if 0 <= self._k <= self.n:
+ return factorial(self.n) // factorial(self.n - self._k)
  return ZZ.zero()
 
  def random_element(self):
@@ -5684,11 +5682,8 @@ def cardinality(self):
  for i in mset_list:
  d[i] = d.get(i, 0) + 1
 
- c = factorial(len(lmset))
- for i in itervalues(d):
- if i != 1:
- c //= factorial(i)
- return ZZ(c)
+ return ZZ(multinomial(d.values()))
+
 
 class Permutations_set(Permutations):
  """

src/sage/combinat/words/morphism.py

@@ -90,7 +90,6 @@
 # ****************************************************************************
 from __future__ import print_function
 
-import six
 from six.moves import range
 import itertools
 
@@ -393,7 +392,7 @@ def __init__(self, data, domain=None, codomain=None):
  self._morph = {}
 
  dom_alph = list()
- for (key,val) in six.iteritems(data):
+ for key, val in data.items():
  dom_alph.append(key)
  if val in codomain.alphabet():
  self._morph[key] = codomain([val])
@@ -474,7 +473,7 @@ def _build_codomain(self, data):
  Finite words over {0, 1, 2}
  """
  codom_alphabet = set()
- for key,val in six.iteritems(data):
+ for key, val in data.items():
  try:
  it = iter(val)
  except Exception:
@@ -490,7 +489,7 @@ def __hash__(self):
  sage: hash(WordMorphism('a->ab,b->ba')) # random
  7211091143079804375
  """
- return hash(tuple((k,v) for k,v in six.iteritems(self._morph))) ^ hash(self._codomain)
+ return hash(tuple((k,v) for k,v in self._morph.items())) ^ hash(self._codomain)
 
  def __eq__(self, other):
  r"""
@@ -603,7 +602,8 @@ def __str__(self):
  sage: str(s)
  'a->ab, b->ba'
  """
- L = [str(lettre) + '->' + image.string_rep() for lettre,image in six.iteritems(self._morph)]
+ L = [str(lettre) + '->' + image.string_rep()
+ for lettre, image in self._morph.items()]
  return ', '.join(sorted(L))
 
  def __call__(self, w, order=1, datatype=None):
@@ -977,7 +977,7 @@ def __mul__(self, other):
  sage: m * WordMorphism('')
  WordMorphism:
  """
- return WordMorphism(dict((key, self(w)) for (key, w) in six.iteritems(other._morph)), codomain=self.codomain())
+ return WordMorphism(dict((key, self(w)) for key, w in other._morph.items()), codomain=self.codomain())
 
  def __pow__(self, exp):
  r"""
@@ -1082,7 +1082,7 @@ def extend_by(self, other):
  raise TypeError("other (=%s) is not a WordMorphism"%other)
 
  nv = dict(other._morph)
- for k,v in six.iteritems(self._morph):
+ for k, v in self._morph.items():
  nv[k] = v
  return WordMorphism(nv)
 
@@ -1290,7 +1290,7 @@ def images(self):
  sage: sorted(WordMorphism('6->ab,y->5,0->asd').images())
  [word: 5, word: ab, word: asd]
  """
- return list(six.itervalues(self._morph))
+ return list(self._morph.values())
 
  def reversal(self):
  r"""
@@ -1303,7 +1303,7 @@ def reversal(self):
  sage: WordMorphism('a->ab,b->a').reversal()
  WordMorphism: a->ba, b->a
  """
- return WordMorphism(dict((key, w.reversal()) for (key, w) in six.iteritems(self._morph)),codomain=self._codomain)
+ return WordMorphism(dict((key, w.reversal()) for (key, w) in self._morph.items()),codomain=self._codomain)
 
  def is_empty(self):
  r"""
@@ -2186,7 +2186,7 @@ def conjugate(self, pos):
  sage: m.conjugate(2)
  WordMorphism: a->cdeab, b->zxy
  """
- return WordMorphism(dict((key, w.conjugate(pos)) for (key, w) in six.iteritems(self._morph)))
+ return WordMorphism(dict((key, w.conjugate(pos)) for (key, w) in self._morph.items()))
 
  def has_left_conjugate(self):
  r"""

src/sage/data_structures/mutable_poset.py

@@ -150,8 +150,6 @@
 # ****************************************************************************
 from __future__ import print_function
 
-from six import itervalues
-
 from sage.structure.sage_object import SageObject
 
 
@@ -1690,7 +1688,7 @@ def _copy_shells_(self, other, mapping):
  self._null_ = other._null_._copy_all_linked_(memo, self, mapping)
  self._oo_ = memo[id(other._oo_)]
  self._shells_ = {f.key: f for f in iter(memo[id(e)] for e in
- itervalues(other._shells_))}
+ other._shells_.values())}
 
  def copy(self, mapping=None):
  r"""
@@ -1771,7 +1769,7 @@ def shells(self, include_special=False):
  """
  if include_special:
  yield self.null
- for e in itervalues(self._shells_):
+ for e in self._shells_.values():
  yield e
  if include_special:
  yield self.oo

src/sage/databases/conway.py

@@ -19,7 +19,7 @@
 # http://www.gnu.org/licenses/
 #*****************************************************************************
 
-from six import itervalues, iteritems
+from six import iteritems
 from six.moves import cPickle as pickle
 
 import collections
@@ -168,7 +168,7 @@ def __len__(self):
  return self._len
  except AttributeError:
  pass
- self._len = sum(len(a) for a in itervalues(self._store))
+ self._len = sum(len(a) for a in self._store.values())
  return self._len
 
  def __iter__(self):

src/sage/graphs/graph.py

@@ -6975,7 +6975,7 @@ def cores(self, k=None, with_labels=False):
  if with_labels:
  return core
  else:
- return list(six.itervalues(core))
+ return list(core.values())
 
  @doc_index("Leftovers")
  def modular_decomposition(self, algorithm='habib'):

src/sage/knots/link.py

@@ -48,7 +48,6 @@
 # ****************************************************************************
 from __future__ import division
 
-import six
 from six.moves import range
 
 from sage.matrix.constructor import matrix
@@ -1340,7 +1339,7 @@ def pd_code(self):
  else:
  crossing_dic = {}
 
- pd = list(six.itervalues(crossing_dic))
+ pd = list(crossing_dic.values())
  self._pd_code = pd
  return self._pd_code
 

src/sage/matroids/constructor.py

@@ -97,13 +97,11 @@
 # Distributed under the terms of the GNU General Public License (GPL)
 # as published by the Free Software Foundation; either version 2 of
 # the License, or (at your option) any later version.
-# http://www.gnu.org/licenses/
+# https://www.gnu.org/licenses/
 #*****************************************************************************
 
 from __future__ import absolute_import
 
-from six import itervalues
-
 from itertools import combinations
 from sage.matrix.constructor import Matrix
 from sage.graphs.all import Graph
@@ -917,7 +915,7 @@ def revlex_sort_key(s):
 
  if groundset is None:
  groundset = set()
- for X in itervalues(CC):
+ for X in CC.values():
  for Y in X:
  groundset.update(Y)
 

src/sage/misc/sage_input.py

@@ -174,7 +174,7 @@
 
 from __future__ import print_function, absolute_import
 
-from six import itervalues, iteritems, integer_types, string_types
+from six import iteritems, integer_types, string_types
 
 
 def sage_input(x, preparse=True, verify=False, allow_locals=False):
@@ -1915,7 +1915,7 @@ def _sie_referenced(self):
  """
  refs = self._sie_args[:]
  refs.append(self._sie_func)
- refs.extend(itervalues(self._sie_kwargs))
+ refs.extend(self._sie_kwargs.values())
  return refs
 
  def _sie_format(self, sif):

src/sage/modular/pollack_stevens/manin_map.py

@@ -43,7 +43,7 @@
 # http://www.gnu.org/licenses/
 #*****************************************************************************
 from __future__ import print_function, absolute_import
-from six import itervalues, iteritems
+from six import iteritems
 from six.moves import range
 
 from sage.rings.continued_fraction import convergents
@@ -712,7 +712,7 @@ def normalize(self):
  (1 + O(11^2), 2 + O(11))
  """
  sd = self._dict
- for val in itervalues(sd):
+ for val in sd.values():
  val.normalize()
  return self
 

src/sage/modules/multi_filtered_vector_space.py

@@ -38,7 +38,7 @@
 # the License, or (at your option) any later version.
 # https://www.gnu.org/licenses/
 # ****************************************************************************
-from six import iteritems, itervalues
+from six import iteritems
 
 from sage.rings.all import QQ, ZZ, Integer
 from sage.rings.infinity import infinity, minus_infinity
@@ -84,11 +84,11 @@ def MultiFilteredVectorSpace(arg, base_ring=None, check=True):
  base_ring = QQ
  else:
  filtration = dict(arg)
- F = next(itervalues(arg))  # the first filtration
+ F = next(iter(arg.values())) # the first filtration
  dim = F.dimension()
  if base_ring is None:
  base_ring = F.base_ring()
- for deg in filtration.keys():
+ for deg in filtration:
  filt = filtration[deg]
  if filt.base_ring() != base_ring:
  filt = filt.change_ring(base_ring)

src/sage/schemes/elliptic_curves/ell_curve_isogeny.py

@@ -63,7 +63,6 @@
 # https://www.gnu.org/licenses/
 # ****************************************************************************
 from __future__ import print_function, absolute_import
-from six import itervalues
 from six.moves import range
 
 from copy import copy
@@ -2087,12 +2086,12 @@ def __compute_via_velu(self, xP, yP):
  a3 = self.__E1.a3()
 
  # next iterate over the 2torsion points of the kernel
- for Qvalues in itervalues(ker_2tor):
+ for Qvalues in ker_2tor.values():
  (tX, tY) = self.__velu_sum_helper(Qvalues, a1, a3, xP, yP)
  X = X + tX
  Y = Y + tY
 
- for Qvalues in itervalues(ker_non2tor):
+ for Qvalues in ker_non2tor.values():
  (tX, tY) = self.__velu_sum_helper(Qvalues, a1, a3, xP, yP)
  X = X + tX
  Y = Y + tY
@@ -2158,11 +2157,11 @@ def __init_kernel_polynomial_velu(self):
 
  psi = poly_ring(1)
 
- for Qvalues in itervalues(self.__kernel_2tor):
+ for Qvalues in self.__kernel_2tor.values():
  xQ = invX(x=Qvalues[0])
  psi = psi*(x - xQ)
 
- for Qvalues in itervalues(self.__kernel_non2tor):
+ for Qvalues in self.__kernel_non2tor.values():
  xQ = invX(x=Qvalues[0])
  psi = psi*(x - xQ)