<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><br><div><div>On Apr 13, 2011, at 9:25 AM, Adrian Scherzinger wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div>hi<br><br>i have to make wind maps on a certain height above ground with gradsdods <br>and the nomads gfs_hd (0.5) data. To solve this, i use the zinterp.gs <br>function for an area which is quite big (lat 40 70, lon -15 40). The <br>calculation of one timestep takes around 20 minutes.<br></div></blockquote><div>That's because you've made a large 3-D request from a GDS of data in GRIB2 format, which takes a long time, especially if you are using 'gradsdods', an old deprecated build, which is not optimized for doing I/O from an opendap server. You are doing the I/O on row by row basis, slamming the server with small requests. zinterp.gs is not designed to work with remote data sets. </div><div><br></div><br><blockquote type="cite"><div>however, after one or two timesteps, the zinterp.gs function just takes <br>a few seconds and gradsdods just delivers "entire grid empty" data.<br>the same script with nomads gfs 1 degree or 2.5 degree data is working <br>fine for all timesteps.<br></div></blockquote>It may be because the server has enabled a DOS after your 20 minutes of 1-row requests. The administrator of the nomads GDS may be willing to check the logs for an explanation of why your data requests are failing. </div><div><br></div><div>My suggestion: </div><div>1. Upgrade to the latest version of GrADS</div><div>2. Use a separate script to create a local data set (using fwrite or sdfwrite) that is the subset of gfs_hd grid, only the lat/lon/levels that you need for zinterp.gs to work. Optimize this for hitting the server a minimum number of times, and don't ask for more than one level per request -- that will slow down your script. </div><div>3. After you have a created a local data set, then run zinterp.gs. </div><div><br></div><div>--Jennifer</div><div><br></div><div><br></div><div><br></div><div><br><blockquote type="cite"><div><br>what is going wrong?<br><br>thanks for any help<br>adrian<br><br>-- <br>___________________________<br>Adrian Scherzinger<br>Stv. Leiter Wetterprognosen<br><br>Genossenschaft METEOTEST<br>Fabrikstrasse 14, CH-3012 Bern<br>Tel +41 (0)31 307 26 26<br>Fax +41 (0)31 307 26 10<br><a href="mailto:adrian.scherzinger@meteotest.ch">adrian.scherzinger@meteotest.ch</a><br>http://www.meteotest.ch<br><br>******************************************************************<br>METEOFON - Wetterauskünfte im direkten Dialog mit dem Prognostiker<br>0900 57 61 52 (CHF 3.13/Min ab Festnetz) So-Fr 5-17:30, Sa 5-13:30<br>******************************************************************<br><br>_______________________________________________<br>gradsusr mailing list<br>gradsusr@gradsusr.org<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></body></html>