Converting grads binary dat to txt file

[K.Kamala]

dear Grads users,

We want to convert netcdf  file to .txt
We want output format to be in floating instead of exponential.
we used following commands in script.

sdfopen data.nc
set lat 20
set lon 70
set t 1 10
set gxout print
set prnopts %10.3f 1 1
 d myvar


then the output file is as follows

Printing Grid -- 10 Values -- Undef = 2e+20
     0.000
     0.000
     0.000
     0.000
     0.000
     0.000
     0.000
     0.000
     0.000
     0.000

 Please help.