Re: [Tftb-help] finding the energy in a certain time and frequency interval in a TF plot

[Francois Auger]

Dear Hallgrímur,
In a TFR matrix, the time is in columns, and the frequency bins are in lines
(The first line is the zero frequency (DC), and the last one is the highest
(one half of the sampling frequency).
Best regards,

To select the area between the 10th and the 50th time sample, and the
frequency between the 60th and the 80th frequency bin, use
TFR(10:50,60:80)

By the way, where on earth are you living ?

best regards,

At 22:50 09/05/2007, Hallgrímur Th. Björnsson wrote:
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> Hi.
>
> I am using the Time Frequency Toolbox in Matlab 
> for my Masters thesis. It is working very well 
> and I have been using the Choi Williams 
> Distribution to great effect working on EEG signals.
>
> What I like to do is to find the total energy in 
> a certain part of the plot (for ex. All energy 
> in 10-12 Hz from time 0 to 1 sec).
> I have been trying to use integ2d.m to do this, 
> but what confuses me is how I interact with the 
> TFR variable returned from tfrcw. How do I only select a subspace of TFR?
>
> Thanks.

Francois Auger,  http://www.univ-nantes.fr/auger-f

Chef du departement Mesures Physiques de l'IUT de Saint-Nazaire
tel : 02 40 17 81 21, internet : http://www.univ-nantes.fr/iutsn/mp

Laboratoire Ireena, Crtt, bureau 272
tel : 02 40 17 26 35, internet : http://www.polytech.univ-nantes.fr/ireena

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