## Mercurial > repos > shellac > sam_consensus_v3

### diff env/lib/python3.9/site-packages/networkx/generators/interval_graph.py @ 0:4f3585e2f14b draft default tip

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"planemo upload commit 60cee0fc7c0cda8592644e1aad72851dec82c959"

author | shellac |
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date | Mon, 22 Mar 2021 18:12:50 +0000 |

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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/env/lib/python3.9/site-packages/networkx/generators/interval_graph.py Mon Mar 22 18:12:50 2021 +0000 @@ -0,0 +1,69 @@ +""" +Generators for interval graph. +""" +from collections.abc import Sequence +import networkx as nx + +__all__ = ["interval_graph"] + + +def interval_graph(intervals): + """ Generates an interval graph for a list of intervals given. + + In graph theory, an interval graph is an undirected graph formed from a set + of closed intervals on the real line, with a vertex for each interval + and an edge between vertices whose intervals intersect. + It is the intersection graph of the intervals. + + More information can be found at: + https://en.wikipedia.org/wiki/Interval_graph + + Parameters + ---------- + intervals : a sequence of intervals, say (l, r) where l is the left end, + and r is the right end of the closed interval. + + Returns + ------- + G : networkx graph + + Examples + -------- + >>> intervals = [(-2, 3), [1, 4], (2, 3), (4, 6)] + >>> G = nx.interval_graph(intervals) + >>> sorted(G.edges) + [((-2, 3), (1, 4)), ((-2, 3), (2, 3)), ((1, 4), (2, 3)), ((1, 4), (4, 6))] + + Raises + -------- + :exc:`TypeError` + if `intervals` contains None or an element which is not + collections.abc.Sequence or not a length of 2. + :exc:`ValueError` + if `intervals` contains an interval such that min1 > max1 + where min1,max1 = interval + """ + intervals = list(intervals) + for interval in intervals: + if not (isinstance(interval, Sequence) and len(interval) == 2): + raise TypeError( + "Each interval must have length 2, and be a " + "collections.abc.Sequence such as tuple or list." + ) + if interval[0] > interval[1]: + raise ValueError( + f"Interval must have lower value first. " f"Got {interval}" + ) + + graph = nx.Graph() + + tupled_intervals = [tuple(interval) for interval in intervals] + graph.add_nodes_from(tupled_intervals) + + while tupled_intervals: + min1, max1 = interval1 = tupled_intervals.pop() + for interval2 in tupled_intervals: + min2, max2 = interval2 + if max1 >= min2 and max2 >= min1: + graph.add_edge(interval1, interval2) + return graph