[Eeglablist] problems with plotting data in eeglab

[Bradley Voytek]

Danielle (and eeg list):

So the reason the output has 43 columns when you have 46 events is as follows:

figure; erp = pop_erpimage(EEG,1, [5],[],strsetname, 4,1,{},[],''
,'yerplabel', '\muV', 'erp', 'on', 'limits', [NaN NaN -25 25 NaN NaN
NaN NaN] , 'cbar', 'on', 'vert',[170 300] ,'topo', { [5] EEG.chanlocs
EEG.chaninfo } );

The sixth input variable in your code, the one after 'strsetname', is
the number 4. This number sets the level of smoothing (for
visualization purposes) across the epochs dimension. The output will
always have that number minus one columns, because you're smoothing
across that dimension.

If you set that number to 0 or 1, your output will have the exact same
number of columns as you have have trials because you're not
smoothing.

Hope that helps!

::brad

On Fri, Jul 17, 2009 at 11:41, Danielle Farrar<dfarrar at bu.edu> wrote:
> Hey EEGLab users,
> I have a further refinement on my question from yesterday.  When I do the
> following:
>
> figure; erp = pop_erpimage(EEG,1, [5],[],strsetname,4,1,{},[],'' ,
> 'yerplabel', '\muV', 'erp', 'on', 'limits',[NaN NaN -25 25 NaN NaN NaN NaN]
> , 'cbar', 'on', 'vert',[170 300] ,'topo', { [5] EEG.chanlocs EEG.chaninfo }
> );
>
> The erp variable now contains a matrix of data with 43 columns.  Since the
> dataset contains 46 events, I was wondering what is contained within these
> 43 columns?  The numbers are close but short a few ...
> It seems that if they contain the data for each trial, I could use matlab to
> average them and then plot the curve directly using matlab, instead of the
> eeglab tools.  My end goal would be to feed this plot to a subplot, and put
> many other datasets on the same figure.
> Does this make sense?  Does anyone have any experience or suggestions for
> this?
> Thanks!
> Danielle Farrar
>
> On Thu, Jul 16, 2009 at 2:23 PM, Danielle Farrar <danielle.farrar at gmail.com>
> wrote:
>>
>> Hey everyone,
>> I'm new to matlab and eeglab, and trying to put together a series of ERP
>> plots to look at and compare a series of them.  I am trying to do a couple
>> of things
>> 1) I would like to be able to extra the single-channel ERP wave
>> (preferably the one from the erp image).  I just want the wave and not the
>> color map.  I would like to them put a series of these in a subplot, to be
>> able to compare them.  I understand how to get the whole image in there,
>> doing something like this:
>> subplot(5,3,2); erp = pop_erpimage(EEG,1, [5],[],'Kip 062909 Control 1
>> Rare',9,1,{},[],'' , 'yerplabel', '\muV', 'erp', 'on', 'limits',[NaN NaN -25
>> 25 NaN NaN NaN NaN] , 'cbar', 'off', 'vert',[170 300] );
>> However, I would really prefer *just* to insert the erp average wave - I
>> have a large series of waves to plot and there isn't enough space to include
>> the color image as well.
>> Also, I would like to be able to overlay a couple of different
>> waves/averages.  For instance, I have four waves -- two representing the
>> ERPs from common stimulus, two representing the ERPs from the rare stimulus.
>>  I would like to be able to group them into averages, and then put them on
>> the same plot.  It seems like the ERP average/compare tool either lets you
>> average them *all* or it lets you average them all individually, but I would
>> like to be able to combine/overlay two averages.
>> Thanks so much for your help in advance.
>> Danielle
>
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