color bar not agreeing with data

Jim Li megjim1 at GMAIL.COM
Wed Jul 29 18:10:44 CEST 2009

Dear Fieldtripper:

I am puzzled by the output from "multiplotTFR". The colorbar doesn't look right 
at all! Can anyone help me?

Basicly I have a data structure caled "TF" that's calculated from 
FREQANALYSIS. I ran the following script and got a plot (see attachment)

>> cfg              = []; cfg.layout  = '4D248.lay'; cfg.interactive  = 'yes'; 
cfg.showlabels = 'yes'; 
cfg.colorbar      = 'yes'; cfg.renderer=  'zbuffer'

cfg = 

         layout: '4D248.lay'
    interactive: 'yes'
     showlabels: 'yes'
       colorbar: 'yes'
       renderer: 'zbuffer'

the input is freq data with 248 channels, 141 frequencybins and 77 timebins
reading layout from file 4D248.lay

Now, when running " max(max(max(max(TF.powspctrm(:,:,:,:)))))" I got :

ans =


This is order of magnitude larger than the colorbar maximum, which is 1.82e-
24 (see attachment) . Why should this discrepency happen? Why the data 
maximum is not plotted?

The same happened to the minimum: when running "min(min(min(min
(TF.powspctrm(:,:,:,:)))))" I got  5.393784644607502e-034, which is about 8 
orders of magnitude smaller than the colorbar minimum (2.12e-26 according to 
the attached figure). This I can understand since small numbers should be 
sacrificed to  save bandwidth for more significant numbers. 

BTW I tried "singleplotTFR" and got the same discrepency between data 
maximum and plot/colorbar maximum for a channel. They differ by about an 
order of magnitude, which is huge!

FYI, I was working directly before my PC, not through VNC or Remote 
Desktop connection.

Thanks a lot,


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