IntervalGraph generator and a bug in is_chordal

[nathanncohen]

Hello !!!

This very small patch creates an independent generator for IntervalGraph, which is then called by the old RandomIntervalGraph function... The function is_chordal is fixed, as it was not exploring the whole graph when it was not connected.

Nathann

Component: graph theory

Author: Nathann Cohen

Reviewer: Robert Miller

Merged: sage-4.5.alpha1

Issue created by migration from https://trac.sagemath.org/ticket/8284

[nathanncohen]

comment:2

oh yes, and the lex_bfs method now admits an optional initial vertex ! :-)

[rlmill]

comment:3

Can you please provide a doctest which shows a simple example of creating an IntervalGraph from intervals?

[nathanncohen]

comment:4

Done ! :-)