# HG changeset patch
# User Nathann Cohen <nathann.cohen@gmail.com>
# Date 1284711349 -7200
# Node ID 41683cf9f3d151c02d628f8a12289fa993722532
# Parent 1d2358ac1804797838cd25182d5c88ea97bf0eec
trac 9930 - Additional test in is_even_hole_free
diff -r 1d2358ac1804 -r 41683cf9f3d1 sage/graphs/graph.py
a
|
b
|
|
1354 | 1354 | sage: print "Everything is Fine !" |
1355 | 1355 | Everything is Fine ! |
1356 | 1356 | |
| 1357 | TESTS: |
| 1358 | |
| 1359 | Bug reported in #9925, and fixed by #9420:: |
| 1360 | |
| 1361 | sage: g = Graph(':SiBFGaCEF_@CE`DEGH`CEFGaCDGaCDEHaDEF`CEH`ABCDEF') |
| 1362 | sage: g.is_even_hole_free() |
| 1363 | False |
| 1364 | sage: g.is_even_hole_free(certificate = True) |
| 1365 | Subgraph of (): Looped multi-graph on 4 vertices |
| 1366 | |
| 1367 | Making sure there are no other counter-examples around :: |
| 1368 | |
| 1369 | sage: t = lambda x : (Graph(x).is_forest() or |
| 1370 | ... isinstance(Graph(x).is_even_hole_free(certificate = True),Graph)) |
| 1371 | sage: all( t(graphs.RandomBipartite(10,10,.5)) for i in range(100) ) |
| 1372 | True |
| 1373 | |
1357 | 1374 | REFERENCE: |
1358 | 1375 | |
1359 | 1376 | .. [ABCHRS08] L. Addario-Berry, M. Chudnovsky, F. Havet, B. Reed, P. Seymour |