AFNI Message Board

Dear AFNI users-

We are very pleased to announce that the new AFNI Message Board framework is up! Please join us at:

https://discuss.afni.nimh.nih.gov

Existing user accounts have been migrated, so returning users can login by requesting a password reset. New users can create accounts, as well, through a standard account creation process. Please note that these setup emails might initially go to spam folders (esp. for NIH users!), so please check those locations in the beginning.

The current Message Board discussion threads have been migrated to the new framework. The current Message Board will remain visible, but read-only, for a little while.

Sincerely, AFNI HQ

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nick
March 12, 2013 02:37PM
Hi Laurel,

Laurel GD Wrote:
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> Our voxels are in 1x1x1mm space and we used an NN
> =3 for the 2d GUI. An rmm = 3 doesn't seem to give
> us the same results

NN=3 means that voxels are considered neighbours if they share a side, edge or corner.
In this case, with isotropic voxels, you can easily translate this into rmm through Pythagorus' theorem: two voxels are neighbours if their distance is equal or less than sqrt(3), or approximately 1.731 (sqrt meaning square root).

To prevent rounding errors it is actually better to take a slightly higher value, for example rmm=1.75. As an exercise you may consider why, in this case, every value rmm=x with sqrt(3) <= x < 2 should do the job.

best,
Nick
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Subject Author Posted

rendering clusterize ?

Laurel GD March 11, 2013 07:42PM

Re: rendering clusterize ?

rick reynolds March 12, 2013 10:53AM

Re: rendering clusterize ?

Laurel GD March 12, 2013 01:54PM

Re: rendering clusterize ?

nick March 12, 2013 02:37PM