Re: Filtering Matrix

[Juan Pablo Carbajal]

On Sun, Mar 24, 2013 at 4:17 PM, christorno
<address@hidden> wrote:
> Hi!
> Im trying to analyse a wavfile:s matrix with the wavread command. The Wav
> file is a recording of a magnet passing through several spoils and by
> induction creating a electric spike. The magnet passes through several of
> them and I want to analyse the time between these fluxuations.
> The matrix gives me values say between -5 to 5 and I want to find where it's
> 0, so I can get the time between the spoils!
>
> Does anyone know how to do this?
> Thanks!
>
>
>
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if your data is in matrix A you can try
idx = find(A==0)

Of course, that wont work if the data is noisi, so maybe you prefer to
define a threshold
thr = 0.05*max(abs(A))
idx = find (abs(A)<=thr)