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<br><div><div>On Feb 22, 2008, at 6:16 PM, Ryo Furue wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Hi Jennifer,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Thank you for your help.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">| The seg fault happens when you try to display the 3-dimensional</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">| variable tr with the Z dimension set to something other than 1. That</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">| is a bug in the sdfopen code in GrADS 1.9. That code is no longer in</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">| version 2.0, and I am unlikely to spend any time debugging it since</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">| the problem is readily fixed if you use a 'dtype netcdf' descriptor</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">| file:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Um, I'm a bit confused.<span class="Apple-converted-space"> </span>I guess you say two things:</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">1. The bug is fixed in 2.0 and you don't want to fix it in the 1.9</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><span class="Apple-converted-space"> </span>series.</div></blockquote></div><div><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><span class="Apple-style-span" style="-webkit-text-stroke-width: -1; ">2. The bug can be circumvented in GrADS 1.9 by using a 'dtype netcdf'</span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><span class="Apple-converted-space"> </span>descriptor file.</div></blockquote><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Correct?</div></blockquote>Yes.</div><div><br></div><div><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><span class="Apple-style-span" style="-webkit-text-stroke-width: -1; ">I certainly understand that you don't want to fix a bug</span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">in an old version that is already fixed in a newer one.</div></blockquote> It's not that the bug is fixed, it's that the buggy I/O code in sdfopen is completely gone. Just think of 2.0 as the fix for the problems in 1.9. Bugs in 2.0 will be fixed as quickly as possible. </div><div><br><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">But, creating a descriptor file for a netCDF file is like</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">adding English subtitles to an English-speaking movie!</div></blockquote><div>I disagree. Many self-describing files have inadequate metadata and clients such as GrADS and Ferret have difficulty handling them without any guidance. Descriptor files give the user control over which metadata to use and how to interpret the data. Without that option you are handicapped by what the data provider put in the file. Consider the file you submitted -- none of your variables has a 'long_name'. Wouldn't you consider that important piece of information about the data in your file? </div><div><br class="webkit-block-placeholder"></div><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">(They are useful for people with hearing disability,</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><span class="Apple-converted-space"> </span>but that's not the point here . . .)<span class="Apple-converted-space"> </span>Anyway, I can live</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">with the workaround.<span class="Apple-converted-space"> <span class="Apple-style-span" style="-webkit-text-stroke-width: -1; ">I don't want to push this case.</span></span></div></blockquote>OK. I will let it go too, because I could rant for a long time about bad metadata in self-describing files... </div><div><br class="webkit-block-placeholder"></div><div><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><span class="Apple-style-span" style="-webkit-text-stroke-width: -1; ">| So, unless GrADS bothers to transpose the temperature array</span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">|<span class="Apple-converted-space"> </span></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">| GrADS bothers to do this when you have 'options zrev' in your</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">| descriptor file or 'positive down' as a netcdf attribute.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><br></div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Aha!<span class="Apple-converted-space"> </span>Thanks for the explanation.<span class="Apple-converted-space"> </span>That's clear.<span class="Apple-converted-space"> </span>Probably GrADS</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">doesn't actually transpose arrays on memory (which would be some</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">extra computation, which isn't really necessary), but it presents</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">such a "view" to the user.<span class="Apple-converted-space"> </span></div></blockquote>That's right. By the way, you can always use 'set yflip' if you want to draw your z-axis upside down. </div><div><br><blockquote type="cite"><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><span class="Apple-converted-space"> </span>My confusion was because I'm not</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">familiar with that view.<span class="Apple-converted-space"> </span>I usually use Ferret, where array indices</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">never change whether the axis is positive down or not.</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">The attribute "positive down" affects only how Ferret plots</div><div style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">the field.</div></blockquote>That is one of many subtle differences between the two programs. It can be little confusing to go back and forth between them. </div><div><br></div><div>--Jennifer</div><div><br class="webkit-block-placeholder"></div><div>--</div><div><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; "><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>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></span> </div><br></body></html>