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<p style="margin-top:0;margin-bottom:0">Dear Mary</p>
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<p style="margin-top:0;margin-bottom:0">Thank you for the very clear and informative response!</p>
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<p style="margin-top:0;margin-bottom:0">Kind regards<br>
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<pre>Athanasios F. Karagiannidis<br>Physicist, PhD Meteorology and Climatology<br>E-mail: thankar@live.com</pre>
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<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> Mary Haley <haley@ucar.edu><br>
<b>Sent:</b> Friday, December 22, 2017 7:42 PM<br>
<b>To:</b> Athanasios Karagiannidis<br>
<b>Cc:</b> ncl-talk@ucar.edu<br>
<b>Subject:</b> Re: [ncl-talk] exact location of a lat/lon coodrinates in the grid-box</font>
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<div class="x_gmail_default" style="font-size:small">Dear Athanasios,</div>
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<div class="x_gmail_default" style="font-size:small">It depends.</div>
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<div class="x_gmail_default" style="font-size:small">There are three contouring methods: AreaFill (the default), RasterFill, and CellFill.</div>
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<div class="x_gmail_default" style="font-size:small">For these methods, lat=20, lon=20 will represent the center of the box, except for one special case.</div>
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<div class="x_gmail_default" style="font-size:small">For RasterFill, if you set sfXArray and sfYArray to arrays that have one more element than the dimensions of your data array, then the lat/lon points will represent the corners of a box, rather than the center.</div>
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<div class="x_gmail_default" style="font-size:small">I've created a sample NCL script that shows the three methods, plus the fourth RasterFill method with the corners method. This script uses dummy data, so you should be able to run it as is.</div>
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<div class="x_gmail_default" style="font-size:small">--Mary</div>
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<div class="x_gmail_quote">On Fri, Dec 22, 2017 at 10:20 AM, Athanasios Karagiannidis via ncl-talk
<span dir="ltr"><<a href="mailto:ncl-talk@ucar.edu" target="_blank">ncl-talk@ucar.edu</a>></span> wrote:<br>
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<p class="x_MsoNormal"><span lang="EN-US">Dear sirs/madams</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">I have a question that I’m going to formulate it using an example:</span></p>
<p class="x_MsoNormal"><span lang="EN-US">Let’s say I have a dataset (Lat, Lon, T). The grid is 1x1 degree. One of the many points may be Lat=20, Lon=20, T=10.</span></p>
<p class="x_MsoNormal"><span lang="EN-US">The question is: When ncl draws a map of T, what does the Lat=20, Lon=20 represents? The center of the 1x1 degree grid-box? Or maybe a corner? For example, if Lat=20, Lon=20 is the southwest corner of the 1x1 grid-box,
then the center of the grid-box is at Lat=20.5, Lon=20.5.</span></p>
<p class="x_MsoNormal"><span lang="EN-US"> </span></p>
<p class="x_MsoNormal"><span lang="EN-US">Kind regards</span></p>
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<pre>Athanasios F. Karagiannidis<br>Physicist, PhD Meteorology and Climatology<br>E-mail: <a href="mailto:thankar@live.com" target="_blank">thankar@live.com</a></pre>
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