Thanks Doug. I could do it in a linux with GrADS 1.9b4. But I think this version is not available for IBM/AIX (ncar supercomputers like bluevista), so I could not do that there. Please correct me if I am wrong. <br> A related question which comes from the above is following:
<br>I have the following three control files and the corresponding binary files are more than 1.5 GB. <br>199701_01-09_2D.ctl<br>199701_10-19_2D.ctl<br>199701_20-31_2D.ctl<br>So I have total 4.5 GB. Using cat to make a single file does not work (since grads cannot handle more than 2 GB). Is there any way I can open three files, and do some calculation simultaneously!!! When I tried there is a gap as expected in the figure generated using three data files.
<br>Any help would be appreciated.<br> <br><br><br><br><div><span class="gmail_quote">On 2/26/07, <b class="gmail_sendername">Douglas Clark</b> <<a href="mailto:dbcl@ceh.ac.uk">dbcl@ceh.ac.uk</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
John,<br><br>Assuming that your files have 9 or 10 days' of data in each, I think you'll need to use the CHSUB option - see GrADS index<br> <a href="http://grads.iges.org/grads/gadoc/gadocindex.html">http://grads.iges.org/grads/gadoc/gadocindex.html
</a><br>under control file > options > template (or the likes).<br><br>With your current template, the way the template works is such that every day's data is assumed to be in a different file - because you have %d2 in the template. So when you set the time to 1997/01/01, GrADS looks for data in a file called 199701_01-01_2D.dat, which doesn't exist - so it says all values are undefined (arguably it might be more useful if GrADS said "can't find file" at this point, but it doesn't). With time 1997/01/02, GrADS looks for data in a file called 199701_02-02_2D.dat, and so on.
<br><br>I think CHSUB will come to your rescue (although I have never used it myself). You need a ctl file with something along the lines of<br>DSET ^199701_%ch_2D.dat<br>CHSUB 1 9 01-09<br>CHSUB 10 19 10-19<br>CHSUB 20 31 20-31
<br>OPTIONS template<br><br>The first two integers on each CHSUB line will depend on the time step given in yout TDEF line - I have assumed daily data. See the GrADS documentation for details.<br><br>Doug<br><br><br>>>>
<a href="mailto:johnguhin@GMAIL.COM">johnguhin@GMAIL.COM</a> 26/02/2007 07:14 >>><br> Hi,<br> I have three files like these....<br>199701_01-09_2D.ctl<br>199701_10-19_2D.ctl<br>199701_20-31_2D.ctl<br><br>I wrote a control file like this...
<br>dset ^199701_%d2-%d2_2D.dat<br>options template<br>................................................<br><br>I can open the control file, but while plotting it says<br>Cannot contour grid - all undefined values<br><br>But I can plot from individual files. Where am I doing wrong?
<br><br>--<br>John Guhin<br><br><br>--<br>This message (and any attachments) is for the recipient only. NERC<br>is subject to the Freedom of Information Act 2000 and the contents<br>of this email and any reply you make may be disclosed by NERC unless
<br>it is exempt from release under the Act. Any material supplied to<br>NERC may be stored in an electronic records management system.<br></blockquote></div><br><br clear="all"><br>-- <br>John Guhin