Thanks Jennifer, I will take a look at this. Unfortunately the netCDF is a necessity because the graphics are generated on the fly based on coordinates passed in based on a user's mouse click on an image. Using netCDF the image takes ~1 second to generate and the grib2 takes closer to 15 seconds as a result of the increased I/O. I will let you know how it goes. That EDEF sounds great; I guess I have been away from GrADS for too long. Thanks so much.<br>
<br>Matt<br><br><div class="gmail_quote">On Mon, Mar 17, 2008 at 4:22 PM, Jennifer Adams <<a href="mailto:jma@cola.iges.org">jma@cola.iges.org</a>> wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
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<br><div><div class="Ih2E3d"><br></div>It should do the trick, since you'll be using the 'dtype netcdf' code path from 1.9, which is more robust. </div><div><div class="Ih2E3d"> <br><br></div>This is a GREAT example for using the E dimension to simplify your analysis! Here are excerpts from your 5D descriptor file: </div>
<div><br></div><div>dset ^%e.nc</div><div>options template</div><div>tdef 67 linear 00z16mar2008 6hr</div><div>edef 7</div><div>00 61 12z17mar2008</div><div>01 61 06z17mar2008</div><div>02 61 00z17mar2008</div><div>03 61 18z16mar2008</div>
<div>04 61 12z16mar2008</div><div>05 61 06z16mar2008</div><div>06 61 00z16mar2008</div><div>endedef</div><div><br></div><div>The tdef statement describes a single time axis that spans all 7 ensembles (which are reallly forecasts with different initial times). </div>
<div><br></div><div>An additional simplification might be to skip the conversion to NetCDF -- you can read the grib2 files directly, templating over T and E. Once you've done the conversion, though, I/O will be faster with NetCDF, especially if X and Y don't vary. But definitely use EDEF instead of 'set dfile 'n. There's a lot more analysis you can do when your ensembles are not separate data sets. </div>
<div><br></div><font color="#888888"><div>Jennifer</div></font><div class="Ih2E3d"><div><br></div><br></div><div class="Ih2E3d"><div> <span style="border-collapse: separate; border-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; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"><span style="border-collapse: separate; border-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; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px;"><span style="border-collapse: separate; border-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; text-indent: 0px; text-transform: none; white-space: normal; 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" target="_blank">jma@cola.iges.org</a></div><div><br>
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