From: Dennis Shea <shea_at_nyahnyahspammersnyahnyah>

Date: Mon, 3 Apr 2006 12:03:03 -0600 (MDT)

Date: Mon, 3 Apr 2006 12:03:03 -0600 (MDT)

*>Is there an easy way to compute mode (statistic) in NCL?
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*>It would be nice if there was a dim_mode function.
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*>For example, if I have a variable var(lat,lon,time), how can
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*>I get the mode for each grid point (mode(lat,lon))?
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*>
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Conceptually easy .... Not so, in practice,

See Numerical Recipies "Estimation of the Mode ..."

Are the data guaranteed to be unimodal?

What to do if you have bimodal data?

--- http://mathworld.wolfram.com/StatisticalMedian.html "An interesting empirical relationship between the mean, median, and mode which appears to hold for unimodal curves of moderate asymmetry is given by mean-mode = [approx] 3(mean-median)" Hence, mode = mean - 3(mean-median) mean = dim_avg_Wrap(..) median = dim_median(..) mode = mean ; transfer meta data mode = mean - 3*(mean-median) mode_at_long_name = "mode [approximate]" mode@info = "http://mathworld.wolfram.com/StatisticalMedian.html" mode_at_equation = "mean - 3*(mean-median)" printVarSummary(mode) Good luck D _______________________________________________ ncl-talk mailing list ncl-talk_at_ucar.edu http://mailman.ucar.edu/mailman/listinfo/ncl-talkReceived on Mon Apr 03 2006 - 12:03:03 MDT

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