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<div style="direction: ltr;font-family: Tahoma;color: #000000;font-size: 10pt;">Dear NCL users/developers,<br>
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I ran into a problem with ncl (v.6.3.0) using the function gc_inout. I used the function to identify grid points on a gaussian grid (512x256) within a polygon. When the polygon has a zonal extent larger than 180 degrees and extends over the equator (covers
partly both northern and southern hemispheres), a problem occurs; on the edges gridpoints are missing that should have been identified.
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<div>I attached 2 simple idealized plots that demonstrate the issue; all gridpoints should be identified within the boxes:<br>
plot1) box lon-100:100, lat 10:30; everything fine<br>
plot2) box lon-100:100, lat -10:10; gridpoints on both edges are missing<br>
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Is this a bug or a known issue as the description of gc_inout says: "and that the vertices can be contained in a hemisphere"?<br>
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<div>Any suggestions how can I work around this issue?<br>
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Looking forward to suggestions!<br>
Cheers,<br>
Andries</div>
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