<div dir="ltr"><div class="gmail_default" style="font-size:small">You are trying to take 1-dimensional random data and treat it as a 2D rectilinear grid, which assumes that you have the same latitudes across each longitude dimension, and the same longitudes across each latitude dimension.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">This is not going to work, because your data is not rectilinear.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">Unfortunately, the gsn_csm_vector_xxxxx functions don&#39;t currently allow you to draw vectors at random points.</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">We have a special function called wmvectmap that do what you want:</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small"><a href="http://www.ncl.ucar.edu/Document/Functions/Built-in/wmvectmap.shtml">http://www.ncl.ucar.edu/Document/Functions/Built-in/wmvectmap.shtml</a></div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default" style="font-size:small">See example weather_sym_9.ncl at:</div><div class="gmail_default" style="font-size:small"><br></div><div class="gmail_default"><a href="http://www.ncl.ucar.edu/Applications/weather_sym.shtml">http://www.ncl.ucar.edu/Applications/weather_sym.shtml</a><br></div><div class="gmail_default"><br></div><div class="gmail_default">--Mary</div><div class="gmail_default"><br></div><div class="gmail_default"><br></div><div class="gmail_default" style="font-size:small"><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Jun 20, 2017 at 6:55 PM, Zhu CE <span dir="ltr">&lt;<a href="mailto:lovingzhuce@163.com" target="_blank">lovingzhuce@163.com</a>&gt;</span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial"><div style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial"><div style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial"><div style="line-height:1.7;color:#000000;font-size:14px;font-family:Arial"><div>Hi everyone,</div><div><br></div><div>I want to draw observed winds from scatter stations in windbarb.</div><div><br></div><div>I used <i>onedtond</i> function to convert wind data from 1-D to 2-Ds, and assign latitude and longitude to the new 2-Ds wind data&#39;s coordinate.</div><div><br></div><div>Finally, I used <i>gsn_csm_vector(wks,uWND,<wbr>vWND,resV) </i>to draw windbarbs.</div><div><br></div><div>NCL tells me that &quot;<i>warning:VectorFieldSetValues: irregular coordinate array vfXArray non-monotonic: defaulting vfXArray</i>&quot;, &quot;<i>warning:VectorFieldSetValues: irregular coordinate array vfYArray non-monotonic: defaulting vfYArray</i>&quot;, and I got a wrong plot.</div><div><br></div><div>Attachments are my NCL script, the data, the wrong plot and the right plot I want.</div><div><br></div><div>Any mistakes I had done? Could you help me? Thanks!</div></div><br><br><span title="neteasefooter"><p> </p></span></div><br><br><span title="neteasefooter"><p> </p></span></div><br><br><span title="neteasefooter"><p> </p></span></div><br><br><span title="neteasefooter"><p> </p></span></blockquote></div><br></div>