<div dir="ltr">Keep in mind that it's generally a good idea (but is not strictly required) that the following relationship is held in the XDEF and YDEF lines:<div><br></div><div>max_x = min_x + dx*nx</div><div>max_y = min_y + dy*ny</div><div><br></div><div>What I usually do is find the maximum and minimum latitudes and longitudes anywhere in the geographic domain and then divide the difference in those by whatever you set for NX or NY. Use that as the step value. XDEF and YDEF are largely cosmetic for irregular grids, though. What is most important for getting your data to show up correctly is having a PDEF entry with the correct values for whatever your projection is. If your data are not projected in a way that Grads can support then I'm not sure you can do this using GrADS.</div><div><br></div><div>Jeff Duda</div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Thu, Jun 20, 2019 at 1:46 AM wendi harjupa <<a href="mailto:wendiharjupa@gmail.com">wendiharjupa@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">Dear GrADS users,<div><br></div><div>I need your help with this problem.</div><div>I have two-dimensional data, which have no linear resolution, such below;</div><div><br></div><div>1. The first, second, third and the last coordinate longitude data are 21.2887, 121.29860, 121.30840 and 148.76140, respectively.</div><div>2. The first, second, third and the last coordinate latitude data are 22.70906, 22.70909, 22.70911 and </div><div>46.19549, respectively.</div><div><br></div><div>I want to make the control file for the data to plot it by grads,</div><div><br></div><div>XDEF LEVEL 2800 121.28870 XXXX</div><div>YDEF LEVEL 2400 22.70906 YYYY</div><div><br></div><div>What number should I use to change XXXX and YYYY?</div><div>and is there special command should I use to handle the irregular spatial resolution?</div><div><br></div><div>Very appreciate for your help.</div><div>Thank you very much.</div><div>Best regards,</div><div>wendi</div><div> <br></div><div><br></div><div><br></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Wed, Jun 19, 2019 at 9:17 PM wendi harjupa <<a href="mailto:wendiharjupa@gmail.com" target="_blank">wendiharjupa@gmail.com</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"><div dir="ltr">Dear GrADS user,<div><br></div><div>I want to plot the data which has irregular lon and lat...</div><div>I donot want to interpolate the data, so I just want to plot it as the original data.</div><div><br></div><div>My question is how to make the control file for the irregular lon and lat data.</div><div>I attach two data through this email,</div><div>1. asci data which shows the different of lon and lat of the data.</div><div>2. Binary format data of the asci data.</div><div><br></div><div>Thank you very much for your help.</div><div><br></div><div>best regards</div><div>wendi</div><div class="gmail_chip gmail_drive_chip" style="width:396px;height:18px;max-height:18px;background-color:rgb(245,245,245);padding:5px;font-family:arial;font-weight:bold;font-size:13px;border:1px solid rgb(221,221,221);line-height:1"><a href="https://drive.google.com/file/d/1HDCQXO30JwIRCaxTL-H1pf6eibRvhTpp/view?usp=drive_web" style="display:inline-block;max-width:366px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;text-decoration-line:none;padding:1px 0px;border:none" target="_blank"><img style="vertical-align: bottom; border: none;" src="https://ssl.gstatic.com/docs/doclist/images/icon_10_generic_list.png"> <span dir="ltr" style="vertical-align:bottom;text-decoration:none">RDCA20150803_0305.bin</span></a><img style="opacity: 0.55; float: right; display: none;"></div><div class="gmail_chip gmail_drive_chip" style="width:396px;height:18px;max-height:18px;background-color:rgb(245,245,245);padding:5px;font-family:arial;font-weight:bold;font-size:13px;border:1px solid rgb(221,221,221);line-height:1"><a href="https://drive.google.com/file/d/1l0vSZLO0Z21aBlfuMLF2UJM02m0kXTtC/view?usp=drive_web" style="display:inline-block;max-width:366px;overflow:hidden;text-overflow:ellipsis;white-space:nowrap;text-decoration-line:none;padding:1px 0px;border:none" target="_blank"><img style="vertical-align: bottom; border: none;" src="https://ssl.gstatic.com/docs/doclist/images/icon_10_generic_list.png"> <span dir="ltr" style="vertical-align:bottom;text-decoration:none">RDCA20150803_0305.txt</span></a><img style="opacity: 0.55; float: right; display: none;"></div></div>
</blockquote></div>
_______________________________________________<br>
gradsusr mailing list<br>
<a href="mailto:gradsusr@gradsusr.org" target="_blank">gradsusr@gradsusr.org</a><br>
<a href="http://gradsusr.org/mailman/listinfo/gradsusr" rel="noreferrer" target="_blank">http://gradsusr.org/mailman/listinfo/gradsusr</a><br>
</blockquote></div><br clear="all"><div><br></div>-- <br><div dir="ltr" class="gmail_signature"><div dir="ltr"><div><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><div dir="ltr"><font size="2"><span>Jeff Duda, Research Scientist</span></font></div><div dir="ltr"><font size="2"><span></span></font>University of Colorado Boulder</div><div dir="ltr"><font size="2"><span></span></font>Cooperative Institute for Research in Environmental Sciences</div><div dir="ltr">NOAA/OAR/ESRL/Global Systems Division<br><font size="2"><span>
<span>Boulder, CO<br></span></span></font>
</div></div></div></div></div></div></div></div>