problem w/ cfg.highlight using topoplot to show samples in sig clusters

Andrew Smart at NYU.EDU
Wed Aug 29 20:02:14 CEST 2007

Hi Ingrid again,
Inspecting the variables more I find that the output of the timelockstatistics on
my data gives:
28 pos clusters and 36 neg clusters (1 significant pos cluster and 1 sig neg

and posclusterslabelmat and negclusterslabelmet as 267x301 (where does this
size come from if my sample rate is 600?)

then using
pos = stat.posclusterslabelmat==1;
neg = (stat.negclusterslabelmat==1)*(-1);

pos and neg are obviously 267x301,
and I can find the elements of pos and neg that = 1 and = -1 respectively.
elements =1 are spread out between roughly pos(59:168,149:172) and =-1
between neg(152:240,242:270).

however, using

pos_int = mean(pos(:,m(k):m(k+1))')';
neg_int = mean(neg(:,m(k):m(k+1))')';

in the for loop, gives pos_int as 267x1 but all the elements are zeros.

and in neg_int some elements are values like -0.1667 for example.

so for the highlight to work do the values in pos_int and neg_int have to be
either 1 or -1?

i have tried various parameters in m and but nothing i have tried seems to
work. i am stuck!


----- Original Message -----
From: Ingrid Nieuwenhuis <ingrid.nieuwenhuis at FCDONDERS.RU.NL>
Date: Wednesday, August 29, 2007 5:12 am
Subject: Re: [FIELDTRIP] problem w/ cfg.highlight using topoplot to show
samples in sig clusters

> Hi Andrew,
> You can find the option cfg.highlight in the function topoplot.m, this
> function is called by topoplotER (also by topoplotTFR by the way). It
> should
> contain the channel numbers which you want to highlight.
> Why your plot doesn't give any highlighted sensors is hard to say without
> knowing your data (what did you give in to timelockstatistics with which
> cfg).
> - It could be that the time you plot (0:0.05:0.5) does not contain the
> clusters
> - It could be the specification of m [1:15:301], this is exactly
> copied from
> the tutorial, but it is based on the sample frequency of the data used
> there. In the tutorial a second of data is used, cut up in 21 pieces from
> 0:0.05:1 and that data has a sample frequency of 301 also cut up in 21
> pieces 1:15:301. You should adjust m to you own time settings and sample
> frequency.
> - cfg.highlight = find(pos_int==1|neg_int==-1), what is the outcome of
> this?
> For the highlighting to work it should contain the sensor numbers to be
> highlighted. If your m is not specified correctly I would guess that pos_int
> and neg_int are not specified correctly and cfg.highlight turnes up empty
> and therefore no highlights are plotted.
> Hope this give you some ideas to find out what's wrong.
> Good luck,
> Ingrid
> -----Original Message-----
> From: FieldTrip discussion list [

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