# Re: Reading an ASCII file

```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

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

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

```