Re: Creating a new variable of indeterminate length

This is a *much* less detailed answer than Jonathan's.
A simpleton approach.

===
(1) Are you writing netCDF?

(2) Are all stations supposed to provide observations at (say) 6 hour
intervals?

(3) All report the same variables p,u,v,t,q,......

(4) Some of the stations may not report each time period?

nsta = 1000
nday = 366 ; max number of days
nhr = 4
klev = 26 ; if more than 1 level

ntim = nday*nhr

The following generates arrays with missing values

staName = new( nsta, "string", "")
staId = new( nsta, "integer", -999)
t = new( (/nsta,ntim,klev/), "float", 1e20)
u = ...
v = ...
z = ...
etc

nid = -1

; loop read data (NAME, ID, T, ...)

   ii = ind(staId.eq.ID) ; does an entry already exist?
   if (ismissing(ii(0))) then
       nid = nid + 1
       staName(nid) = NAME
       staId(nid) = ID
   else
       nid = ii(0)
   end if

   nt = ???
   t(nid,nt,:) = T
   u(nid,nt,:) = U

end loop

   system("/bin/rm -f FOO.nc")
   fo = addfile("FOO.nc" , "r")

   fo->STATION_NAME = staName(0:nid) ; write a subset of the data
   fo->STATION_ID = staId(0:nid)
   f0->T = t(0:nid,:,:)

etc

????????

On 9/29/10 2:31 AM, Christopher Steele wrote:
> Hi everyone,
>
> I'm trying to read in a list of meteorological station files and extract
> the relevant data from them as one continuous time series. However, due
> to the nature of meteorological stations, not all report data at each
> time interval so I'm left with data files of varying lengths.
> Ordinarily, I would create a file list, preassign a new variable, and
> create a loop over the files and extract the data into the new variable
> so that I'm left with one continuous data set to work with.
> Unfortunately, I cannot do this if the length of the files are
> indeterminate. Short of going back to the original data files (of which
> there are many) and ensuring that all stations that do not report
> produce a nan, is there a way around this, or even a more efficient way
> of reading in data from multiple files?
>
> cheers
>
> Chris
>
>
>
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Received on Wed Sep 29 15:23:05 2010