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Dear Oga,<br>
<blockquote type="cite"
cite="mid72c0aa42050329165738201123@mail.gmail.com">
<pre wrap="">I am just wondering how I can change the length of
FFT analysis window for computating coherence.
</pre>
</blockquote>
You may use the 'winsize' parameter of the crossf function to set the
window size.<br>
<blockquote type="cite"
cite="mid72c0aa42050329165738201123@mail.gmail.com">
<pre wrap="">And we know the resolution of frequency bins is
determined by the length of FFT analysis window.
Actually running "crossf" automatically determines it
depending on the length of epoch data.
We are now analyzing a data with short length of
epoch (about 150 ms with sampling rate of 2048 Hz),
and want to analyze with about 50 ms (around 128 time points)
or 100 ms (128 time points) even without stepping.
I would like to know how to fix the
FFT analysis winodow and stepping window size
within this short length under using crossf function.
</pre>
</blockquote>
Use "'winsize', 128". You epochs might be too short though. It is
better to use longer data epochs because the crossf function will
reduce the output time range by removing half the window size on both
sides. <br>
<br>
Arno<br>
<br>
<div class="moz-signature">-- <br>
<br>
<b><font face="Arial,Helvetica"> <a target="_blanc"
href="http://www.sccn.ucsd.edu/%7Earno">Arnaud Delorme</a>, Ph.D.</font></b>
, SCCN, UCSD, San Diego, USA
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