sage.graphs: Use yet more block # needs

Author: Matthias Koeppe

src/sage/graphs/generators/classical_geometries.py

@@ -67,14 +67,8 @@ def SymplecticPolarGraph(d, q, algorithm=None):
         (40, 12, 2, 4)
         sage: O.is_isomorphic(G)
         False
-        sage: O.is_isomorphic(G)                # optional - GOT (with --distribution 'sagemath-graphs[modules]')
-        Traceback (most recent call last):
-        ...
-        File "<doctest...>", line 1, in <module>
-        O.is_isomorphic(G)
-        AttributeError: 'function' object has no attribute 'is_isomorphic'
-        sage: S = graphs.SymplecticPolarGraph(6,4,algorithm="gap")      # not tested (long time), needs sage.libs.gap
-        sage: S.is_strongly_regular(parameters=True)    # not tested (long time)        # needs sage.libs.gap
+        sage: S = graphs.SymplecticPolarGraph(6, 4, algorithm="gap")    # not tested (long time)
+        sage: S.is_strongly_regular(parameters=True)                    # not tested (long time)
         (1365, 340, 83, 85)
 
     TESTS::
@@ -273,7 +267,7 @@ def _orthogonal_polar_graph(m, q, sign="+", point_type=[0]):
     `NO^{-,\perp}(5,5)`::
 
         sage: g = _orthogonal_polar_graph(5,5,point_type=[2,3])         # long time, needs sage.libs.gap
-        sage: g.is_strongly_regular(parameters=True)    # long time                     # needs sage.libs.gap
+        sage: g.is_strongly_regular(parameters=True)                    # long time, needs sage.libs.gap
         (300, 65, 10, 15)
 
     `NO^{+,\perp}(5,5)`::
@@ -487,19 +481,22 @@ def NonisotropicOrthogonalPolarGraph(m, q, sign="+", perp=None):
         NO^-,perp(3, 5): Graph on 10 vertices
         sage: g.is_strongly_regular(parameters=True)
         (10, 3, 0, 1)
-        sage: g = graphs.NonisotropicOrthogonalPolarGraph(6,3,'+')      # long time, needs sage.libs.gap
-        sage: g.is_strongly_regular(parameters=True)    # long time                     # needs sage.libs.gap
+
+        sage: # long time, needs sage.libs.gap
+        sage: g = graphs.NonisotropicOrthogonalPolarGraph(6,3,'+')
+        sage: g.is_strongly_regular(parameters=True)
         (117, 36, 15, 9)
-        sage: g = graphs.NonisotropicOrthogonalPolarGraph(6,3,'-'); g   # long time
+        sage: g = graphs.NonisotropicOrthogonalPolarGraph(6,3,'-'); g
         NO^-(6, 3): Graph on 126 vertices
-        sage: g.is_strongly_regular(parameters=True)    # long time                     # needs sage.libs.gap
+        sage: g.is_strongly_regular(parameters=True)
         (126, 45, 12, 18)
-        sage: g = graphs.NonisotropicOrthogonalPolarGraph(5,5,'-')      # long time, needs sage.libs.gap
-        sage: g.is_strongly_regular(parameters=True)    # long time                     # needs sage.libs.gap
+        sage: g = graphs.NonisotropicOrthogonalPolarGraph(5,5,'-')
+        sage: g.is_strongly_regular(parameters=True)
         (300, 104, 28, 40)
-        sage: g = graphs.NonisotropicOrthogonalPolarGraph(5,5,'+')      # long time, needs sage.libs.gap
-        sage: g.is_strongly_regular(parameters=True)    # long time                     # needs sage.libs.gap
+        sage: g = graphs.NonisotropicOrthogonalPolarGraph(5,5,'+')
+        sage: g.is_strongly_regular(parameters=True)
         (325, 144, 68, 60)
+
         sage: g = graphs.NonisotropicOrthogonalPolarGraph(6,4,'+')
         Traceback (most recent call last):
         ...
@@ -871,11 +868,11 @@ def TaylorTwographDescendantSRG(q, clique_partition=False):
         sage: g.is_strongly_regular(parameters=True)
         (27, 10, 1, 5)
         sage: from sage.combinat.designs.twographs import taylor_twograph
-        sage: T = taylor_twograph(3)            # long time                             # needs sage.rings.finite_rings
-        sage: g.is_isomorphic(T.descendant(T.ground_set()[1]))  # long time             # needs sage.rings.finite_rings
+        sage: T = taylor_twograph(3)                            # long time
+        sage: g.is_isomorphic(T.descendant(T.ground_set()[1]))  # long time
         True
-        sage: g = graphs.TaylorTwographDescendantSRG(5)          # not tested (long time)
-        sage: g.is_strongly_regular(parameters=True)             # not tested (long time)
+        sage: g = graphs.TaylorTwographDescendantSRG(5)         # not tested (long time)
+        sage: g.is_strongly_regular(parameters=True)            # not tested (long time)
         (125, 52, 15, 26)
 
     TESTS::
@@ -1198,7 +1195,7 @@ def HaemersGraph(q, hyperoval=None, hyperoval_matching=None, field=None, check_h
         ...
         RuntimeError: incorrect hyperoval
 
-        sage: g = graphs.HaemersGraph(8); g     # not tested (long time)                # needs sage.rings.finite_rings
+        sage: g = graphs.HaemersGraph(8); g             # not tested (long time)        # needs sage.rings.finite_rings
         Haemers(8): Graph on 640 vertices
         sage: g.is_strongly_regular(parameters=True)    # not tested (long time)        # needs sage.rings.finite_rings
         (640, 71, 6, 8)
@@ -1498,9 +1495,9 @@ def OrthogonalDualPolarGraph(e, d, q):
         sage: G.is_distance_regular(True)
         ([7, 6, 4, None], [None, 1, 3, 7])
         sage: G = graphs.OrthogonalDualPolarGraph(0,3,3)        # long time
-        sage: G.is_distance_regular(True)       # long time
+        sage: G.is_distance_regular(True)                       # long time
         ([39, 36, 27, None], [None, 1, 4, 13])
-        sage: G.order()                         # long time
+        sage: G.order()                                         # long time
         1120
 
     REFERENCES:
@@ -1514,7 +1511,7 @@ def OrthogonalDualPolarGraph(e, d, q):
         sage: G.is_distance_regular(True)
         ([14, 12, 8, None], [None, 1, 3, 7])
         sage: G = graphs.OrthogonalDualPolarGraph(-1,3,2)       # long time
-        sage: G.is_distance_regular(True)       # long time
+        sage: G.is_distance_regular(True)                       # long time
         ([28, 24, 16, None], [None, 1, 3, 7])
         sage: G = graphs.OrthogonalDualPolarGraph(1,3,4)
         sage: G.is_distance_regular(True)

src/sage/graphs/generators/distance_regular.pyx

@@ -1418,15 +1418,16 @@ def GeneralisedOctagonGraph(const int s, const int t):
 
     EXAMPLES::
 
-         sage: G = graphs.GeneralisedOctagonGraph(1, 4)                                 # needs sage.libs.gap
-         sage: G.is_distance_regular(True)                                              # needs sage.libs.gap
-         ([5, 4, 4, 4, None], [None, 1, 1, 1, 5])
-         sage: G = graphs.GeneralisedOctagonGraph(2, 4)  # optional - gap_packages internet
-         sage: G.is_distance_regular(True)  # optional - gap_packages internet
-         ([10, 8, 8, 8, None], [None, 1, 1, 1, 5])
-         sage: G = graphs.GeneralisedOctagonGraph(5, 1)                                 # needs sage.libs.gap
-         sage: G.is_distance_regular(True)                                              # needs sage.libs.gap
-         ([10, 5, 5, 5, None], [None, 1, 1, 1, 2])
+        sage: # needs sage.libs.gap
+        sage: G = graphs.GeneralisedOctagonGraph(1, 4)
+        sage: G.is_distance_regular(True)
+        ([5, 4, 4, 4, None], [None, 1, 1, 1, 5])
+        sage: G = graphs.GeneralisedOctagonGraph(2, 4)  # optional - gap_packages internet
+        sage: G.is_distance_regular(True)  # optional - gap_packages internet
+        ([10, 8, 8, 8, None], [None, 1, 1, 1, 5])
+        sage: G = graphs.GeneralisedOctagonGraph(5, 1)
+        sage: G.is_distance_regular(True)
+        ([10, 5, 5, 5, None], [None, 1, 1, 1, 2])
 
     .. NOTE::
 
@@ -1528,13 +1529,14 @@ def GeneralisedHexagonGraph(const int s, const int t):
 
     EXAMPLES::
 
+        sage: # needs sage.libs.gap
         sage: G = graphs.GeneralisedHexagonGraph(5, 5)  # optional - gap_packages internet
         sage: G.is_distance_regular(True)  # optional - gap_packages internet
         ([30, 25, 25, None], [None, 1, 1, 6])
-        sage: G = graphs.GeneralisedHexagonGraph(7, 1)                                  # needs sage.libs.gap
-        sage: G.is_distance_regular(True)                                               # needs sage.libs.gap
+        sage: G = graphs.GeneralisedHexagonGraph(7, 1)
+        sage: G.is_distance_regular(True)
         ([14, 7, 7, None], [None, 1, 1, 2])
-        sage: graphs.GeneralisedHexagonGraph(1, 1)                                      # needs sage.libs.gap
+        sage: graphs.GeneralisedHexagonGraph(1, 1)
         Cycle graph: Graph on 6 vertices
 
     .. NOTE::
@@ -1752,16 +1754,17 @@ def _line_graph_generalised_polygon(H):
 
     EXAMPLES::
 
-         sage: from sage.graphs.generators.distance_regular import \
-         ....: _line_graph_generalised_polygon
-         sage: G = graphs.GeneralisedHexagonGraph(1, 8)                                 # needs sage.libs.gap
-         sage: H = _line_graph_generalised_polygon(G)                                   # needs sage.libs.gap
-         sage: H.is_distance_regular(True)                                              # needs sage.libs.gap
-         ([16, 8, 8, None], [None, 1, 1, 2])
-         sage: G = graphs.GeneralisedHexagonGraph(3, 3) # optional - gap_packages internet
-         sage: H = _line_graph_generalised_polygon(G)   # optional - gap_packages internet
-         sage: G.is_isomorphic(H)                       # optional - gap_packages internet
-         True
+        sage: # needs sage.libs.gap
+        sage: from sage.graphs.generators.distance_regular import \
+        ....: _line_graph_generalised_polygon
+        sage: G = graphs.GeneralisedHexagonGraph(1, 8)
+        sage: H = _line_graph_generalised_polygon(G)
+        sage: H.is_distance_regular(True)
+        ([16, 8, 8, None], [None, 1, 1, 2])
+        sage: G = graphs.GeneralisedHexagonGraph(3, 3) # optional - gap_packages internet
+        sage: H = _line_graph_generalised_polygon(G)   # optional - gap_packages internet
+        sage: G.is_isomorphic(H)                       # optional - gap_packages internet
+        True
 
     REFERENCES:
 
@@ -2416,19 +2419,20 @@ def is_near_polygon(array):
 
     TESTS::
 
+        sage: # needs sage.combinat sage.libs.pari
         sage: from sage.graphs.generators.distance_regular import (
         ....: is_near_polygon, near_polygon_graph)
-        sage: is_near_polygon([7, 6, 6, 4, 4, 1, 1, 3, 3, 7])                           # needs sage.combinat sage.libs.pari
+        sage: is_near_polygon([7, 6, 6, 4, 4, 1, 1, 3, 3, 7])
         (4, (2, 2))
         sage: near_polygon_graph(4, (2, 2))
         Double Grassmann graph (5, 2, 2): Graph on 310 vertices
-        sage: near_polygon_graph(*is_near_polygon([3, 2, 2, 1, 1, 3]))                  # needs sage.combinat sage.rings.finite_rings
+        sage: near_polygon_graph(*is_near_polygon([3, 2, 2, 1, 1, 3]))                  # needs sage.rings.finite_rings
         Generalised hexagon of order (1, 2): Graph on 14 vertices
-        sage: is_near_polygon([16, 12, 8, 4, 1, 2, 3, 4])                               # needs sage.combinat sage.libs.pari
+        sage: is_near_polygon([16, 12, 8, 4, 1, 2, 3, 4])
         (6, (4, 5))
-        sage: is_near_polygon([])                                                       # needs sage.combinat sage.libs.pari
+        sage: is_near_polygon([])
         False
-        sage: is_near_polygon([25, 16, 9, 4, 1, 1, 4, 9, 16, 25])  # JohnsonGraph       # needs sage.combinat sage.libs.pari
+        sage: is_near_polygon([25, 16, 9, 4, 1, 1, 4, 9, 16, 25])  # JohnsonGraph
         False
     """
     from sage.arith.misc import is_prime_power
@@ -2719,21 +2723,23 @@ def distance_regular_graph(list arr, existence=False, check=True):
     TESTS::
 
         sage: graphs.distance_regular_graph([3, 2, 2, 1, 1, 1, 1, 2, 2, 3],             # needs sage.combinat
-        ....: existence=True)
+        ....:                               existence=True)
         True
         sage: graphs.distance_regular_graph([3, 2, 2, 1, 2, 1, 1, 2, 2, 3],
-        ....: existence=True)
+        ....:                               existence=True)
         False
         sage: graphs.distance_regular_graph([18, 16, 16, 1, 1, 9])  # optional - internet gap_packages
         Generalised hexagon of order (2, 8): Graph on 819 vertices
-        sage: graphs.distance_regular_graph([14, 12, 10, 8, 6, 4, 2,                    # needs sage.combinat
-        ....: 1, 2, 3, 4, 5, 6, 7])
+
+        sage: # needs sage.combinat
+        sage: graphs.distance_regular_graph([14, 12, 10, 8, 6, 4, 2,
+        ....:                                1, 2, 3, 4, 5, 6, 7])
         Hamming Graph with parameters 7,3: Graph on 2187 vertices
-        sage: graphs.distance_regular_graph([66, 45, 28, 1, 6, 30])                     # needs sage.combinat
+        sage: graphs.distance_regular_graph([66, 45, 28, 1, 6, 30])
         Graph on 1024 vertices
-        sage: graphs.distance_regular_graph([6,5,5,5,1,1,1,6])                          # needs sage.combinat
+        sage: graphs.distance_regular_graph([6,5,5,5,1,1,1,6])
         Generalised octagon of order (1, 5): Graph on 312 vertices
-        sage: graphs.distance_regular_graph([64, 60, 1, 1, 15, 64], check=True)         # needs sage.combinat
+        sage: graphs.distance_regular_graph([64, 60, 1, 1, 15, 64], check=True)
         Graph on 325 vertices
     """
     from sage.misc.unknown import Unknown