Re: Reading an ASCII file

[<SPILLANE@xxxxxxxxxxxxx>]

Hi Graham, 
        For the example you give 
 
yes? define axis/X=1:5:1 longax ; define axis/T=1:4:1 timax 
yes? define grid/T=timax/X=longax gblock 
yes? file/var=sst/grid=gblock/form=free/col=5 testfile 
 
should read the data. 
yes? list sst 
             SST 
             DATA SET: ./testfile 
             1      2      3      4      5     
             1      2      3      4      5 
 1   / 1:  1.000  2.000  3.000  4.000  5.000 
 2   / 2:  2.000  3.000  4.000  5.000  6.000 
 3   / 3:  4.000  5.000  2.000  4.000  3.000 
 4   / 4:  6.000  3.000  2.100  3.400  8.900 
 
In your real world problem of a longitude axis with 90 degree increments 
is the intent of having 5 rather than 4 points along the xaxis to permit a 
discontinuity at -90?  If so this way of defining the x-axis seems to work. 
 
yes? can data/all 
yes? sp echo '-90 0 90 180 270' >> lonin.d 
yes? define grid/x=longax gx 
yes? file/form=free/g=gx/col=5/var=lonval lonin.d  ! this loads the 5 values 
 
yes? def axis/from_data/mod/x/name=lnax/units=lon lonval 
yes? def grid/x=lnax/t=timax gblock 
 
then read in the data as before 
 
yes? file/var=sst/grid=gblock/form=free/col=5 testfile  
yes? list sst 
             SST 
             DATA SET: ./testfile 
           90W     0E     90E    180E   90W    
             1      2      3      4      5 
 1   / 1:  1.000  2.000  3.000  4.000  5.000 
 2   / 2:  2.000  3.000  4.000  5.000  6.000 
 3   / 3:  4.000  5.000  2.000  4.000  3.000 
 4   / 4:  6.000  3.000  2.100  3.400  8.900 
 
and shade it 
 
yes? shade/set sst 
yes? ppl xaxis,-90,270,45 ; ppl shade 
 
The discontinuity at 90W is apparent. 

NOTE: A repeat of the -90 (rather than 270) in the definition of the x-axis 
gave me a non-monotonic axis message. 
 
If on the other hand there were not a discontinuity at 90W then the fifth 
column would be a redundant repeat of the first and the x-axis would only 
have FOUR points 
 
yes? def axis/x=-90:180:90/mod/units=lon longax 
yes? file/var=sst/grid=gblock/form=free/col=4 testfile 
 
would do the trick. 

Good luck, Mick