[Chimera-users] local cross-correlation coefficient

[Elaine Meng]

Hi Zhihai Li,
The correlation from Fit in Map is defined here:

<http://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/fitmaps/fitmaps.html#correlation>

This is a single value calculated for the whole fit, not a local correlation that would have different values in different places.  The correlation is calculated from two maps.  If you were fitting an atomic structure into a map, a map was simulated from the atomic structure and then compared with the other map.

For *local* correlation between two maps, see command "vop localCorrelation":

<http://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/vop.html#localCorrelation>

This vop command would create a third map containing the local correlation values between your two input maps.  Then you could color the isosurface of one of the input maps to show the different local correlation values in different places, for example with Surface Color (in menu under Tools… Volume Data).
<http://www.rbvi.ucsf.edu/chimera/docs/ContributedSoftware/surfcolor/surfcolor.html>

I hope this helps,
Elaine
----------
Elaine C. Meng, Ph.D. 
UCSF Computer Graphics Lab (Chimera team) and Babbitt Lab
Department of Pharmaceutical Chemistry
University of California, San Francisco

On Jul 6, 2014, at 10:30 PM, 李智海 <21620101152414 at stu.xmu.edu.cn> wrote:

> Hi,
> I performed tool "Fit in map” to calculate the correlation value, i was wondering whether the value is the same as local cross-correlation coefficient (local CCC).
> Thanks in advance for your help!
> Best wishes for you!
> Zhihai Li
>