# HG changeset patch
# User Mike Hansen <mhansen@gmail.com>
# Date 1259660681 28800
# Node ID 4ee5c41a5bc865522c979ff44f3112545cbbbe4c
# Parent 684929bc5c5061f29d85b60058c7e476925314d3
[mq]: trac_7487-review.patch
diff --git a/sage/graphs/graph_generators.py b/sage/graphs/graph_generators.py
a
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b
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3376 | 3376 | As for any interval graph, the chromatic number is equal to |
3377 | 3377 | the clique number :: |
3378 | 3378 | |
3379 | | sage: g = graphs.RandomInterval(15) |
| 3379 | sage: g = graphs.RandomInterval(8) |
3380 | 3380 | sage: g.clique_number() == g.chromatic_number() |
3381 | 3381 | True |
3382 | 3382 | |
… |
… |
|
3391 | 3391 | |
3392 | 3392 | from sage.misc.prandom import random |
3393 | 3393 | |
3394 | | s = lambda x,y : (x,y) if x<=y else (y,x) |
3395 | | intervals = [s(random(), random()) for i in range(n)] |
3396 | | intervals.sort(key=lambda x:x[0]) |
| 3394 | intervals = [tuple(sorted((random(), random()))) for i in range(n)] |
| 3395 | intervals.sort() |
3397 | 3396 | edges = [] |
3398 | 3397 | while intervals: |
3399 | 3398 | x = intervals.pop() |
… |
… |
|
3402 | 3401 | edges.append((x,y)) |
3403 | 3402 | else: |
3404 | 3403 | break |
3405 | | g=graph.Graph(vertices=intervals) |
| 3404 | g = graph.Graph(vertices=intervals) |
3406 | 3405 | g.add_edges(edges) |
3407 | 3406 | return g |
3408 | 3407 | |