def topological_sorting(self): """ Topological sorting. @attention: Topological sorting is meaningful only for directed acyclic graphs. @rtype: list @return: Topological sorting for the graph. """ return sorting.topological_sorting(self)
def topological_sorting(self): """ Topological sorting. @attention: Topological sorting is meaningful only for directed acyclic graphs. @rtype: list @return: Topological sorting for the graph. """ return sorting.topological_sorting(self)
antisymmetric_check(nodes, edges), '\n')
print('- Is the binary relation R transitive?\n-',
transitive_check(nodes, edges), '\n')
print('- Is the binary relation R negatively transitive?\n-',
negatively_transitive_check(nodes, edges), '\n')
print('- Is the binary relation R a complete order?\n-',
complete_order_check(nodes, edges), '\n')
print('- Is the binary relation R a complete preorder?\n-',
complete_preorder_check(nodes, edges), '\n')
# tasks 11, 12
print('The strict relation P:\n')
print(strict_relation(nodes, edges), '\n')
print('The indifference relation I:\n')
print(indifference_relation(nodes, edges), '\n')
# tasks 13
groups, dictionary = topological_sorting(nodes, edges)
if groups is None:
print(
'- Topological sorting can not be done: the binary relation R reduced to one node...\n'
)
else:
print('- Topological sorting:\n')
for group in groups:
print(' ↓', group)
print(' ... where', dictionary, 'are grouped cycles.\n')
# binary relation visualization
draw_graph(nodes, edges)