Hi<br>I have made a script for plotting stream function. The script is as<br><br>&#39;reinit&#39;<br>&#39;set display color white&#39;<br>&#39;clear&#39;<br>&#39;sdfopen D:/ECMWF_Monthly_Mean_data/SP/SPjun.nc&#39;<br>&#39;sdfopen D:/ECMWF_Monthly_Mean_data/wind/<a href="http://windjun.nc">windjun.nc</a>&#39;<br>
count = 1<br>while (count &lt;=5)<br>  &#39;clear&#39;<br>  &#39;set grads off&#39;<br>  &#39;set t &#39;count<br>  &#39;q time&#39;<br>date=subwrd(result,3)<br>hour=substr(date,1,3)<br>day=substr(date,4,2)<br>month=substr(date,6,3)<br>
year=substr(date,9,10)<br>date_str=hour&#39; &#39;day&#39;/&#39;month&#39;/&#39;year<br>&#39;clear&#39;<br>&#39;set display color white&#39;<br>&#39;set map 1 1 6&#39;<br>&#39;set line  1 1 1&#39;<br>&#39;set grads off&#39;<br>
&#39;enable print temp&#39;<br>&#39;define one=1+0*lat&#39;<br>&#39;define um=vint(lev,q*u.2,300)&#39;<br>&#39;define vm=vint(lev,q*v.2,300)&#39;<br>&#39;define psi=fish_psi(um,vm)&#39;<br>&#39;define upsi=-muadv(one,psi)&#39;<br>
&#39;define vpsi=-mvadv(one,psi)&#39;<br>&#39;set cint 2&#39;<br>&#39;d psi/1e7&#39;<br>&#39;set gxout vector&#39;<br>&#39;d skip(upsi,4,4);skip(vpsi,4,4)&#39;<br>*&#39;d upsi;vpsi&#39;<br>**&#39;d skip(um,4,4);skip(vm,4,4)&#39;<br>
&#39;draw title &#39;year&#39;.&#39;month&#39;&#39;<br>&#39;draw string 4.5 0.3 Streamfunction for vertically integrated water vapour flux Unit:(kgs`a-1`n) x 10`a7`n&#39;<br>&#39;print&#39;<br>&#39;disable print&#39;<br>&#39;gxyat -x 1024 -y 840 D:/Transport/Streamplot/new&#39;year&#39;.png&#39;<br>
count = count + 1<br>endwhile<br>&#39;clear&#39;<br><br clear="all">But the results are opposite. Means where it should show negative(positive) values it shows positive (negative).<br><br><br>any suggestion.<br><br><br>