NCL can't perform one simple average with large file? Memory Issue

NCL Community,

I have 14 u and v wind component CRCM files that I would
like to average. I have been trying to create a script
that reads the files in and performs one giant average of
all of the data, but I am running into memory errors. Even
averaging just one file alone gives an error with this
script:

  Error: fatal:NclMalloc Failed:[errno=12]

Script:
;*************************************************
;NARCCAPAVG.ncl
;
;************************************************
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
load
"$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"

;************************************************
begin

;************************************************
; read in multiple netCDF files
;************************************************
diri = "/home/rasmussen/NARCCAP/netCDF/RCM3/" ; directory
where files reside
fils = systemfunc("ls "+diri+"uas_CRCM_*.nc")
nfil = dimsizes(fils)
print(fils)

;*************************Get Variables**********
  f = addfiles (fils, "r")

    UAS = f[:]->uas ; (time,yc,xc)

    printVarSummary(UAS)

;*************************Calculate Average******

    WSPD_AVG = dim_avg_n(UAS,0) ; (lat,lon)
    WSPD_AVG_at_long_name = "mean wind speed"

    printVarSummary(WSPD_AVG)

;************************************************
; output ascii
;************************************************

  fName = "RCM3AVG.txt"
  system("/bin/rm -f "+fName) ; remove if file is present
  asciiwrite (fName , WSPD_AVG)

end

The basic script can read smaller files with less time
steps just fine (8760 steps), but it gives an error with
the files that have 14600 time steps. (3hrly over 5 years)

Variable: UAS
Type: float
Total Size: 940240000 bytes
             235060000 values
Number of Dimensions: 3
Dimensions and sizes: [time | 14600] x [yc | 115] x [xc |
140]
Coordinates:
             time: [8395.125..10220]
             yc: [ 0..5700000]
             xc: [ 0..6950000]
Number Of Attributes: 13
   units : m s-1
   type : instantaneaous
   long_name : Zonal Surface Wind Speed
   standard_name : eastward_wind
   missing_value : 1e+20
   _FillValue : 1e+20
   actual_range : ( -41.18215, 38.8077 )
   add_offset : 0
   scale_factor : 1
   coordinates : lon lat level
   grid_mapping : polar_stereographic
   level_desc : 10 m
   grid_desc : polar_stereographic

I am at a loss to explain why this is happening, but I am
going to have to resolve this problem before I can
continue trying to be able to perform heavier computations
with 14 files.

Is there a way that this
http://www.ncl.ucar.edu/Applications/Scripts/crcm_1.ncl
script can be modified to accommodate what I am trying to
be able to do? This might be the easier route for me since
my FORTRAN abilities are not so stellar.

Any advice is appreciated. This doesn't seem like a
complicated problem compared to the other issues that are
submitted to NCL talk.

Kind regards,

DJ Rasmussen
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Received on Sat Oct 03 2009 - 17:27:48 MDT