# HG changeset patch
# User Nathann Cohen <nathann.cohen@gmail.com>
# Date 1278243971 -7200
# Node ID 099359f37e4d2e274c9cc090f310568c055b9bb0
# Parent 556bb66e4c6dbb92a4ee37c1750d82a5c6298eeb
trac 9422 -- Slightly improving is_forest
diff -r 556bb66e4c6d -r 099359f37e4d sage/graphs/generic_graph.py
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| 1819 | 1819 | sage: seven_acre_wood.is_forest() |
| 1820 | 1820 | True |
| 1821 | 1821 | """ |
| 1822 | | for g in self.connected_components_subgraphs(): |
| 1823 | | if not g.is_tree(): |
| 1824 | | return False |
| 1825 | | return True |
| | 1822 | number_of_connected_components = len(self.connected_components()) |
| | 1823 | |
| | 1824 | return self.num_verts() == self.num_edges() + number_of_connected_components |
| 1826 | 1825 | |
| 1827 | 1826 | def order(self): |
| 1828 | 1827 | """ |
