how to use the MISSING function

["Yogesh K. Tiwari" <ktiwari@xxxxxxxxxxxxxxx>]

Hello Ferret Users,

I have the data which has the missing values and 
the data looks like :

co2 =   _, _, _, _, _, _, _, _, _, _, _, _, _, _,
        _, _, _, _, _, _, _, _,
        _, _, _, _, _, _, _, _, _, _, _, _, _, _,
        _, 368.8943, 368.894, 368.9885,368.9885,
       368.9885, 368.8637, 368.874,368.8583,
       368.8586, 368.894, 368.9882, 368.9879,
       368.9879, 368.8361,368.874, 368.8581, _,
       _, _, _, _, _, _, _, _, _, _, _, _, _, _,
       _, 372.2896,



Here as we can see the missing value is denoted by
the special sign  -'

Is there any way that we can fill this missing 
value by the ferret default missing value -1e34

I am doing some analysis in ferret and ferret 
dosen't like this above missing value and from 
last four days its in hanging position.

If I am using the data which dosen't have the 
missing value, means the data looks like :

co2 = 382.7223, 372.0434, 369.4157, 378.8927,
       373.9405, 378.7924, 380.5195,374.1316,
       379.1323, 380.9348, 372.5852, 378.6689

Then my script works fine and ferret gives the 
result within few minuts.

Here the script is attched which I am using for 
the above data.

Kindly help.

The imediate help would be appreciated much.

Regards,
Yogesh


--

===========================================
Yogesh K. Tiwari,
Max-Planck Institute for Biogeochemistry,
Beutenberg Campus, Hans-Knoell-Strasse 10,
D-07745 Jena,
Germany

Office   : 0049 3641 576 376
Home     : 0049 3641 223 163
Fax      : 0049 3641 577 300
Cell     : 0049 1520 4591 008
e-mail   : yogesh.tiwari@bgc-jena.mpg.de
===========================================
!NOTE :- the following script works fine for the 

!         data points which has no gaps as :
 
!          371.232, 368.224, 371.232, 368.224, 
!
!         and ferret calculations gives 
!         the answere within few minuts 
         
!         BUT if 
!         there is gap in between the data points
!         like 

!         -' -' -' 370.232, 368.224, -'-'-'-'

!         then ferret dosen't gives any answere 
!         even if it is working 4-5 days continue. 

!****************************************************


! open datasets

     set data run_94/ecmwf_co2_jul2003.nc  ! keep the order of datasets
     set data tm3airs_new_July_2003.nc   !   unchanged

! define destination axes from lat and lon in ecmwf_co2_jan2003

     define axis/x/units=longitudes/from_data xlon=lon[d=1]
     define axis/y/units=latitudes/from_data  ylat=lat[d=1]
     define grid/x=xlon/y=ylat gcom

! regrid the tm3co2 in tm3airs_new_January_2003.nc  to the above grid using scat2grid

! define the radius and cutoff values for scat2grid function

     define symbol radius = 0.25   ! ideal values for a 0.25 grid
     define symbol cutoff = 2.0    !  with possible minimum interpolation errors

     let lon_1D   = XSEQUENCE(lon[d=2])
     let lat_1D   = XSEQUENCE(lat[d=2])
     let co2_1D   = XSEQUENCE(tm3co2[d=2])

!define the function to count the observed value in each 1x1 grid

     let obs_count = scatgrid_nobs_xy(lon_1D,lat_1D,x[gx=gcom],y[gy=gcom])

!griding tm3co2 using the mask if there is atleast 10 observations in one grid

     let co2_point = IF obs_count GE 10 THEN\
                     scat2gridgauss_xy(lon_1D,lat_1D,co2_1D,\
                     x[gx=gcom],y[gy=gcom],($radius),($radius),($cutoff),($cutoff))
                     

!     shade co2_point


sp rm -f airs_jul_grided_point_data.nc
save/file=airs_jul_grided_point_data.nc/append  co2_point