<div dir="ltr">I found a work around to the problem - calling gsn_csm_contour for each overlay. I think it works because it assigns a unique plot id to each overlay. The revision new order looks like:<div><br></div><div><div> res2@cnFillOn = False</div><div> res2@cnLinesOn = True</div><div> res2@cnLineThicknessF = 2.</div><div> res2@gsnContourNegLineDashPattern = 1</div><div> res@gsnContourZeroLineThicknessF = 3.</div><div> res2@cnLevelSelectionMode = "ManualLevels"</div><div> res2@cnLevelSpacingF = 5.e10;</div><div> tmp0 = gsn_csm_contour(wks,psi1,res2)</div><div><br></div><div> tmp2 = gsn_csm_contour(wks,psi1,res2)</div><div> tmp4 = gsn_csm_contour(wks,psi1,res2)</div><div> overlay(plot(0),tmp0)</div><div> overlay(plot(2),tmp2)</div><div> overlay(plot(4),tmp4)</div><div> delete(tmp0)</div><div> delete(tmp2)</div><div> delete(tmp4)</div><div><br></div><div> res2@cnLevelSpacingF = 1.e10</div><div> tmp1 = gsn_csm_contour(wks,dpsi,res2)</div><div><br></div><div> tmp3 = gsn_csm_contour(wks,dpsi,res2)</div><div> tmp5 = gsn_csm_contour(wks,dpsi,res2)</div><div> overlay(plot(1),tmp1)</div><div> overlay(plot(3),tmp3)</div><div> overlay(plot(5),tmp5)</div><div> delete(tmp1)</div><div> delete(tmp3)</div><div> delete(tmp5)</div></div><div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Sun, Aug 7, 2016 at 1:14 PM, Adam Herrington <span dir="ltr"><<a href="mailto:adam.herrington@stonybrook.edu" target="_blank">adam.herrington@stonybrook.edu</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><div dir="ltr"><div>Hi all,</div><div><br></div><div>I am struggling with overlaying a single contour plot (called 'tmp0' below) over multiple plots in a panel. The script below results in the error "fatal:NhlAddOverlay: tranform is already an annotation or overlay..."</div><div><br></div><div><div> plot(1) = gsn_csm_contour(wks,dz_m,res1)</div><div> plot(3) = gsn_csm_contour(wks,dy_m,res1)</div><div> res1@tiXAxisString = "Latitude"</div><div> plot(5) = gsn_csm_contour(wks,dy_e,res1)</div><div> delete(res1@tiXAxisString)</div><div><br></div><div> res2@cnFillOn = False</div><div> res2@cnLinesOn = True</div><div> res2@cnLineThicknessF = 2.</div><div> res2@cnLevelSelectionMode = "ManualLevels"</div><div> res2@cnLevelSpacingF = 5.e10;</div><div> tmp0 = gsn_csm_contour(wks,psi1,res2)</div><div><br></div><div> res2@cnLevelSpacingF = 1.e10</div><div> tmp1 = gsn_csm_contour(wks,dpsi,res2)</div><div><br></div><div> overlay(plot(0),tmp0)</div><div> overlay(plot(2),tmp0) ;<-fatal:NhlAddOverlay</div><div> overlay(plot(4),tmp0) ;<-fatal:NhlAddOverlay</div><div> overlay(plot(1),tmp1)</div><div> overlay(plot(3),tmp1) ;<-fatal:NhlAddOverlay</div><div> overlay(plot(5),tmp1) ;<-fatal:NhlAddOverlay</div></div><div>...<br></div><div> gsn_panel(wks,plot,(/3,2/),<wbr>resP)<br></div><div><br></div><div>In terms of finding a solution, I would prefer to keep all the overlays contained in the graphics variable 'plot' so that I can easily perform a panel plot. I don't think the solution provided by Mary Haley in <a href="https://www.ncl.ucar.edu/Support/talk_archives/2013/3802.html" target="_blank">https://www.ncl.ucar.edu/<wbr>Support/talk_archives/2013/<wbr>3802.html</a> would work for me, since gsn_panel draws all the plots at once.<br></div><div><br></div><div>Any help is greatly appreciated!</div><span class="HOEnZb"><font color="#888888"><div><br></div><div>Adam</div><div><br></div><div><br></div><div><br></div></font></span></div>
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