<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div><br></div>Hi Eliezer,<div><br><div><div>On Feb 15, 2009, at 1:07 PM, Eliezer Kanal wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Hello folks -<br><br>I have an experimental paradigm which lasts approximately 40 minutes. I usually just let the MEG run straight, end up with a single fif file, and then do all my analysis on this. We recently switched from 16 bit to a 32 bit architecture (side point: does this mean more accurate recordings? what DOES that mean for the end user?), and I learned something new: the machine will only save files less than 2 GB in size. As such, I now have two files, myFile.fif (2 GB) and myFile_1.fif (~1.6 GB). I have no idea where it split it, behavioral-wise.<br><br>What's the best way to proceed from here? I can't analyze them as they sit, since I can't specify multiple files in mne_process_raw if the files contain different numbers of trials. Is there a program that can concatenate them? Should I just try to use mne_read_raw in matlab and hope matlab doesn't choke on almost 4 GB of data? Any ideas? Thanks -</div></blockquote><div><br></div></div>Lauri's and Dan's emails pretty much answer everything. Regarding Matlab, 16 vs 32 bits do not really make a difference there because the data are usually converted into doubles anyway and are actually 8 bytes per reading. What this practically means is that for large data sets the brute force method of reading everything in at once and then processing it is not feasible but you need to process the data in smaller pieces. In fact, mne_browse_raw/mne_process_raw do exactly this by using a ring buffer data structure.</div><div><br></div><div>Since the split raw data files are really continuous but the data is just located in different files, I have dreamed of changes to mne_browse_raw/mne_process_raw to read the the files automatically as needed without the user knowing about the splitting. There are already tags in the fif files which facilitate this. However, this is something which can be only dreamed of at a the moment ;-) For now, Lauri's and Dan's suggestions using the --gave and --gcov options are the most feasible solution if you are happy with the standard processing.</div><div><br></div><div><br></div><div>- Matti</div><div><br></div><div><br></div><br><br><div apple-content-edited="true"> <span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; "><div style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><span class="Apple-style-span" style="border-collapse: separate; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; -webkit-text-decorations-in-effect: none; text-indent: 0px; -webkit-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">-------------</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; font: normal normal normal 12px/normal Helvetica; min-height: 14px; "><br></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Matti Hamalainen, Ph.D.</font></p><p style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><font face="Helvetica" size="3" style="font: normal normal normal 12px/normal Helvetica; ">Athinoula A. 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