[Met_help] [rt.rap.ucar.edu #90430] History for ASCII2NC

[John Halley Gotway via RT]

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  Initial Request
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Hi，


I'm going to perform veri
cation statistics for forecasts at observation points using Point-Stat. Prior to this, ASCII2NC is helpful in re-formatting of point observations. 


In my case, precipitation with different  accumulation intervals (A3, A6, A24...) would be evaluated with observational precipitation at intervals of 1 hour. I noted that '-config option' can specify some summaries of the fields in the ASCII files. Unfortunately, It doesn't seem to support summation (V8 users guide : 4.1.2). Is there any method to obtain the observation in the same period corresponding to simulations?


Any help from you will be greatly appreciated,


Jiao

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  Complete Ticket History
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Subject: ASCII2NC
From: John Halley Gotway
Time: Mon Jun 03 11:57:38 2019

Jiao,

Wow, that's a great question.  You're right, neither ascii2nc nor
madis2nc
or pb2nc support the computation of a "sum".  But it makes total sense
what
you're trying to do.  I just created a development issue to add this
as a
new option for these tools:
   https://github.com/NCAR/MET/issues/1130

Using the existing releases of MET, one equivalent, but less
convenient
option, would be using ascii2nc to compute an average (mean) rate over
the
period of interest... 3-hour mean, 6-hour mean, and 24-hour mean.  And
when
you run Point-Stat, you could specify a "convert" function to convert
that
rain rate into an accumulation amount interval.  For example, you
could
configure Point-Stat something like this:

fcst = {
   field = [
      { name = "APCP"; level = "A03"; },
      { name = "APCP"; level = "A06"; },
      { name = "APCP"; level = "A24"; }
   ];
}

obs = {
   field = [
      { name = "APCP"; level="A0"; message_type = "GAUGE_MEAN_030000";
convert(x) = x*3; },
      { name = "APCP"; level="A0"; message_type = "GAUGE_MEAN_060000";
convert(x) = x*6; },
      { name = "APCP"; level="A0"; message_type = "GAUGE_MEAN_240000";
convert(x) = x*24; }
   ];
}

Note that for each entry in the obs.field array, I've specified a
convert
function to multiple the values by 3, 6, or 24.  Hope that helps.

Thanks,
John

On Sat, Jun 1, 2019 at 9:08 AM 焦宝峰 via RT <met_help at ucar.edu> wrote:

>
> Sat Jun 01 09:08:14 2019: Request 90430 was acted upon.
> Transaction: Ticket created by nuistjiao at 163.com
>        Queue: met_help
>      Subject: ASCII2NC
>        Owner: Nobody
>   Requestors: nuistjiao at 163.com
>       Status: new
>  Ticket <URL:
https://rt.rap.ucar.edu/rt/Ticket/Display.html?id=90430 >
>
>
>
>
> Hi，
>
>
> I'm going to perform veri cation statistics for forecasts at
observation
> points using Point-Stat. Prior to this, ASCII2NC is helpful in
> re-formatting of point observations.
>
>
> In my case, precipitation with different  accumulation intervals
(A3, A6,
> A24...) would be evaluated with observational precipitation at
intervals of
> 1 hour. I noted that '-config option' can specify some summaries of
the
> fields in the ASCII files. Unfortunately, It doesn't seem to support
> summation (V8 users guide : 4.1.2). Is there any method to obtain
the
> observation in the same period corresponding to simulations?
>
>
> Any help from you will be greatly appreciated,
>
>
> Jiao
>

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