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<p>Hi all<br>
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<p>I send out message yesterday, reporting on a problem with EOF function in ncl. Thanks to many others who helps me, It<br>
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<p>turns out that the EOF function miscalculate the first eof mode (the mean). I did an experiment by removing the mean<span style="font-size:12pt"> from the dataset, then I perform the EOF function and reco</span><span style="font-size:12pt">nstruct the data.
The result is perfect after that. </span></p>
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<p><span style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:16px; background-color:rgb(255,255,255)">This problem won't matter if people is working with anomalies data. However, It will be an issue if people use the EOF as a filter. For example,
if you use EOF to filter the high frequency noise from data set and reconstruct the filtered data. It will cause uncertainty. </span><br>
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<p>So hopefully, someone who is managing the EOF coding can see this message. <span style="font-size:12pt">The function I think is responsi</span><span style="font-size:12pt">b</span><span style="font-size:12pt">le for the problem is eofunc_ts and eofunc</span><span style="font-size:12pt">.​</span></p>
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<p>Best <br>
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<p>Geng Xia<br>
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