igraph-help
[Top][All Lists]

## Re: [igraph] Circular Reingold Tilford on tree is not planar!?

 From: Robert Belleman Subject: Re: [igraph] Circular Reingold Tilford on tree is not planar!? Date: Mon, 27 Jun 2011 17:08:24 +0200 User-agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; en-US; rv:1.9.1.19) Gecko/20110420 SeaMonkey/2.0.14

```Hi Gabor, Tamás,

So it is not possible to derive a circular planar layout from the
RT layout?

Because surely it must be possible to construct a planar circular
layout for any tree?

Do you know an alternative?

Thanks,
-- Rob

Tamás Nepusz wrote:
```
```
```
```it should be planar, AFAIK. If it is not planar, that means that the
original non-circular one is not planar
```
```No, it isn't necesarily planar. A while ago I found a graph for which
the RT layout was planar but the circular RT layout wasn't, and I also
thought it was a bug, but it isn't. Try this graph for instance (given
as an edge list):

0-1, 0-2, 0-3, 0-4, 0-5, 0-6, 0-7, 0-8, 0-9, 4-10, 9-10

When you use vertex 0 as root, the RT layout is planar but the circular
RT layout isn't.

--
T.

```
```, the circular one is just the
transformation of that. Can you send us (in private if it's big, to
Tamas and me) an example? I think this is a bug.

Best,
Gabor

On Fri, Jun 24, 2011 at 9:55 AM, Robert Belleman <address@hidden
```
```Hi,

I am applying the circular Reingold Tilford layout algorithm on a tree
consisting of 23k nodes and the same number of edges. I was expecting
this
algorithm to produce a planar layout but it doesn't.

Can anybody enlighten me?

Thanks,
-- Rob

--
Robert Belleman, PhD, Computational Science, Faculty of Science
Universiteit van Amsterdam, Science Park 904, 1098 XH Amsterdam
The Netherlands. T: +31 20 525 7272/7463 F: +31 20 525 7490

_______________________________________________
igraph-help mailing list
https://lists.nongnu.org/mailman/listinfo/igraph-help
```
```

--
KFKI RMKI

_______________________________________________
igraph-help mailing list
https://lists.nongnu.org/mailman/listinfo/igraph-help
```
```

_______________________________________________
igraph-help mailing list
```