<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Whenever you submit a question, it is impossible to answer without knowing two things: the version of GrADS you are running, and the platform you are running it on. THIS REALLY MATTERS! <div><br></div><div>Your 'subset' file should be 10242422568 bytes (399*279*31*742*4) </div><div>If it is not, then you can blame mm5_to_grads.sh -- maybe it doesn't have the capability to write out a 9.5Gb file... Try breaking up your output into 742 separate files and template them together with GrADS. </div><div><br><div>The error messages you're getting indicate that GrADS is having trouble moving to the correct position in the file to fulfill your I/O request. Older versions of GrADS did not have the capability to read files > 2GB, but who can tell whether this is your problem because you didn't provide enough information about your GrADS build. </div><div><br></div><div>--Jennifer</div><div><br></div><div><div><br><div><div>On Nov 18, 2010, at 8:42 AM, Matias Mendez wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>Dear GrADS users,<br><br>I have a big MM5 output (~100GB, with 31 sigma-levels, 742 hourly time<br>steps, 23 variables). I have used mm5_to_grads.sh to extract a<br>variable (u-wind). After that I tried to display this variable,<br>everything was working fine but when I did:<br><br>d u(t=623)<br><br>I got the following error mesage:<br><br>Notice: Automatic Grid Interpolation Taking Place<br>Low Level I/O Error: Seek error on data file<br> Data file name = /home/XXXXX/U_ENE-2006.dat<br>523 rc=-1 fpos=-2145136144 pfi->fhdr=-1<br> Error occurred when seeking to byte 9390016<br>Data Request Error: Error for variable 'u'<br> Error ocurred at column 1<br>DISPLAY error: Invalid expression<br> Expression = u(t=623)<br><br>What does this mean this message and how can I solve this problem?.<br>Is there another way to extract a variable from a big file?. Any<br>sugesstion is welcome. Thanks in advance.<br><br>Best regards,<br>Matías<br><br>P.S.<br>This is the ctl file created by mm5_to_grads.sh<br><br>dset /home/XXXXX/U_ENE-2006.dat<br>byteswapped<br>title MM5 data<br>undef -9999.<br>pdef 399 279 lcc 24.00 -102.00 200.00 140.00 30.00 60.00 -102.00 900<br>0. 9000.<br>xdef 972 linear -121.69 0.0405<br>ydef 571 linear 12.15 0.0405<br>zdef 31 levels<br> 0.99950<br> 0.99800<br> 0.99600<br> 0.99400<br> 0.99200<br> 0.98950<br> 0.98700<br> 0.98500<br> 0.98300<br> 0.98100<br> 0.97500<br> 0.96000<br> 0.94000<br> 0.92000<br> 0.90500<br> 0.89000<br> 0.87000<br> 0.85000<br> 0.83000<br> 0.81000<br> 0.79000<br> 0.76000<br> 0.72000<br> 0.68000<br> 0.64000<br> 0.61000<br> 0.55000<br> 0.45000<br> 0.35000<br> 0.20000<br> 0.05000<br>tdef 742 linear 00:00Z01JAN2006 60MN<br>vars 1<br>u 31 99 u wind (m/s)<br>endvars<br><br>_______________________________________________<br>gradsusr mailing list<br><a href="mailto:gradsusr@gradsusr.org">gradsusr@gradsusr.org</a><br>http://gradsusr.org/mailman/listinfo/gradsusr<br></div></blockquote></div><br><div apple-content-edited="true"> <span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 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; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><span class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 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; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-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; border-spacing: 0px 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; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><div>--</div><div>Jennifer M. Adams</div><div>IGES/COLA</div><div>4041 Powder Mill Road, Suite 302</div><div>Calverton, MD 20705</div><div><a href="mailto:jma@cola.iges.org">jma@cola.iges.org</a></div><div><br class="khtml-block-placeholder"></div><br class="Apple-interchange-newline"></span></span></div></span> </div><br></div></div></div></body></html>