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Dear all,<br><br>I want to pad out my signal before applying some filters while<br>reading the data from the original ds-file.<br><br>at line 578 of the preprocessing.m function it says:<br><br>begsample = cfg.trl(i,1) - begpadding;<br><br>Now because my signal starts at sample 1, begsample will have a negative value of course<br>which results in the warning message<br><br>warning('cannot apply enough paddig at begin of file');<br><br>Does that mean, that fieldtrip cannot pad out the signal at the beginning without<br>throwing away the equivalent of the signal in itself?<br><br>if cfg.trl(i,1) = 2400 and if begpadding = 1200 this should work, because begsample = 1200, right?<br>But that would also mean that for padding I would loose 1200 samples.<br><br>Now let's assume I would like to pad the signal to -25 sec and + 25 sec at the beginning and end.<br>Why does the padding at the beginning require I throw away 25 sec, while the padding at the end doesn't?<br><br>Any clarification on this issue would be greatly appreciated.<br><br>Have a nice day.<br><br>Fred<br><br>-- <br>Frédéric Roux, PhD student<br>Department of Neurophysiology<br>Max Planck Institute for Brain Research<br>D-60529 Frankfurt am Main<br>Frederic.Roux@brain.mpg.de<br>+49(0)69630183225<br><br><br> </div></body>
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