Layout algorithms

Jun 10, 2012 at 6:03 PM

Hello to everybody. After importing some data from a Twitter User`s network (note that the network is huge with about 40.000 edges) .When i presh the ''Show Graph'' button using the Fruchterman-Reingold algorithm ,i receive a good visualization of the Graph (even if it takes some time because of the numerous edges). 

However, when i use the ''Harel-Koren Fast Multiscale'' algorithm which is faster than the Fruchterman-Reingold , i always receive the message below

''the computer does not have enough memory to lay out the graph. Try the following ot fix the problem...'' 

I don`t understand why i get this message everytime i try to use the ''Harel-Koren Fast Multiscale'' algorithm ,whereas when i use the Fruchterman-Reingold algorithm i am not facing such problems. Could you help me?

Jun 10, 2012 at 6:09 PM

It's because the Harel-Koren algorithm requires more memory than the Fruchterman-Reingold algorithm.  Your computer has enough memory to run the Fruchterman-Reingold algorithm on your 40,000-edge graph, but not enough to run the Harel-Koren algorithm on the same graph.

The entire message is this:

The computer does not have enough memory to lay out the graph.  Try the following to fix the problem:

1. Select a different layout algorithm.

2. Close other programs.

3. Restart the computer.

4. Reduce the number of edges in the graph.

5. Add more memory to the computer.

-- Tony

Jun 10, 2012 at 6:17 PM

Thank you for your helpful answer!! I had kind of ''guessed'' that the Harel-Koren might require more memory than the Fruchterman-Reingold but i needed the comfirmation from an expert. Thanxa again.


Conserning the alternative solutions ,i am thinking of adding more memory to my computer. I am using a Dell Inspiron 15R ,Intel  Pentium(R) CPU  P6000@ 1.87GHz 1.86GHz with 3GB of RAM. Operating system: Windows 7, 64-bit


It is obvious that the above memory is not enough to run the Harel-Koren algorithm in such a huge network. How much memory do you think would be sufficient to run the algorithm in this network (20.000 vertices, 40.000 edges approximately) ?

Jun 10, 2012 at 6:37 PM

The more the better!

You may want to consider other issues as well.

More RAM is best made use of when using a 64 bit version of Windows.  You may be (most users are) running a 32 bit version.  An upgrade may be in order.

Your motherboard may also limit the amount of RAM you can use, minimally it will probably allow you to install 8 GB.  Some motherboards allow for much more.  The newer the machine, the more likely it allows for larger RAM sizes.