<div dir="ltr"><div>If I understand you question correctly:   <font face="arial, sans-serif"><span style="color:rgb(0,0,0)">d(T)/dlon <br></span></font></div><div><font face="arial, sans-serif"><span style="color:rgb(0,0,0)">--------</span></font></div><div><b><a href="https://www.ncl.ucar.edu/Applications/gradients.shtml">https://www.ncl.ucar.edu/Applications/gradients.shtml</a></b></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, Sep 3, 2024 at 5:07 PM Hui Ding via ncl-talk <<a href="mailto:ncl-talk@mailman.ucar.edu">ncl-talk@mailman.ucar.edu</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 Sir or Madam, <div><font face="arial, sans-serif">I note that the function gradsf can calculate gradients along longitude and latitude. I wonder about the sign of the gradient. For example, as to <span style="color:rgb(0,0,0)"> </span><a href="https://www.ncl.ucar.edu/Document/Functions/Built-in/igradsf.shtml" style="margin:0px;padding:0px;text-decoration-line:none;color:rgb(0,64,255)" target="_blank"><strong style="margin:0px;padding:0px">igradsf</strong></a><span style="color:rgb(0,0,0)"> (T_grad_lon, T_grad_lat, T),  does T_grad_lon equals d(T)/dlon or -1*</span></font><span style="color:rgb(0,0,0);font-family:arial,sans-serif">d(T)/dlon? The same question for T_grad_lat. </span></div><div><span style="color:rgb(0,0,0);font-family:arial,sans-serif">Thank you!</span></div><div><span style="color:rgb(0,0,0);font-family:arial,sans-serif">Best regards, </span></div><div><span style="color:rgb(0,0,0);font-family:arial,sans-serif">Hui Ding </span></div><div><span style="color:rgb(0,0,0);font-family:arial,sans-serif"><br></span></div><div><span style="color:rgb(0,0,0);font-family:arial,sans-serif"><br></span></div><div><span style="color:rgb(0,0,0);font-family:arial,sans-serif"><br></span></div></div>
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