Finding cycles and Graph::Base

[ctcgag@hotmail.com]

William Goedicke <goedicke@goedsole.com> wrote:

> Dear Y'all -
>
> Has anybody come up with a way of finding cycles in graphs created
> with Graph::Base?

I don't know Graph::Base specifically, but an easy way to find
cycles, if performance isn't a huge concern, is:


foreach $e (edge()) {
my ($v1,$v2)=get_vertices($e);
delete($e);
if (is_path($v1,$v2)) {
restore($e);
edge_is_in_cycle($e);
}
else {
restore($e);
};
};

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[ctcgag@hotmail.com]

William Goedicke <goedicke@goedsole.com> wrote:

> Dear Y'all -
>
> Has anybody come up with a way of finding cycles in graphs created
> with Graph::Base?

I don't know Graph::Base specifically, but an easy way to find
cycles, if performance isn't a huge concern, is:


foreach $e (edge()) {
my ($v1,$v2)=get_vertices($e);
delete($e);
if (is_path($v1,$v2)) {
restore($e);
edge_is_in_cycle($e);
}
else {
restore($e);
};
};

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[ctcgag@hotmail.com]

[email]ctcgag@hotmail.com[/email] wrote:

> William Goedicke <goedicke@goedsole.com> wrote:

> > Dear Y'all -
> >
> > Has anybody come up with a way of finding cycles in graphs created
> > with Graph::Base?

>
> I don't know Graph::Base specifically, but an easy way to find
> cycles, if performance isn't a huge concern, is:

Maybe I should clarify, the below-used subs are just names I made
up to describe the necessary funtionality, not actually existing subs
in any package I know of (and is_path() would have been better called
are_connected()). Although I suspect all of the functionality
would be available in some way or another through Graph::Base.

>
> foreach $e (edge()) {
> my ($v1,$v2)=get_vertices($e);
> delete($e);
> if (is_path($v1,$v2)) {
> restore($e);
> edge_is_in_cycle($e);
> }
> else {
> restore($e);
> };
> };

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[ctcgag@hotmail.com]

[email]ctcgag@hotmail.com[/email] wrote:

> William Goedicke <goedicke@goedsole.com> wrote:

> > Dear Y'all -
> >
> > Has anybody come up with a way of finding cycles in graphs created
> > with Graph::Base?

>
> I don't know Graph::Base specifically, but an easy way to find
> cycles, if performance isn't a huge concern, is:

Maybe I should clarify, the below-used subs are just names I made
up to describe the necessary funtionality, not actually existing subs
in any package I know of (and is_path() would have been better called
are_connected()). Although I suspect all of the functionality
would be available in some way or another through Graph::Base.

>
> foreach $e (edge()) {
> my ($v1,$v2)=get_vertices($e);
> delete($e);
> if (is_path($v1,$v2)) {
> restore($e);
> edge_is_in_cycle($e);
> }
> else {
> restore($e);
> };
> };

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