rostam / GTea

Online version of GraphTea
http://www.graphtheorysoftware.com/
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Added a very naive planarity test, which we mainly use for correctness when implenting the faster algorithm #8

Closed HKH515 closed 7 years ago

rostam commented 7 years ago

I am thinking of the planar visualization after checking that a graph is planar. I am not sure how hard it would be.

HKH515 commented 7 years ago

We were planning on implementing a faster algorithm for planarity testing which runs in quadratic time, i think the problem of finding an embedding is a somewhat harder problem.

The algorithm we were thinking of implement is described in chapter 6 in the following PDF

https://cs.uwaterloo.ca/~biedl/research/pdfs/2017_08_CS762_notes.pdf

HKH515 commented 7 years ago

(note that our current planarity testing algorithm runs in exponential time)

sureshkako commented 7 years ago

Planar visualizations are really interesting one. If we try to implement it is really good. It will be very very useful for our further thinking the characterization of graphs.

On Sun, Oct 1, 2017 at 8:38 PM, Mohammad Ali Rostami < notifications@github.com> wrote:

I am thinking of the planar visualization after checking that a graph is planar. I am not sure how hard it would be.

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rostam commented 7 years ago

@HKH515 Yes, I checked your algorithm. It takes long for even a graph with 10 vertices. It is still good to have. The planarity test and visualization is a hard problem for sure. I saw the article you sent. I am not sure if you can implement this algorithm in the time of your project. Please update your branches to the changes that I did before implementing further.

@sureshkako Sure, there are a lot of algorithms to visualize a planar graph. I need to look at them and see which one is good to implement.