convert .dat file to .nc file
Added by kunal bali over 6 years ago
Dear CDO users,
How can I convert the attached .dat file to .nc file?
please let me know if you have any idea.
Thank You
Replies (3)
RE: convert .dat file to .nc file - Added by Karin Meier-Fleischer over 6 years ago
Hi Kunal,
the way to convert would be to create a gridfile
gridtype = lonlat gridsize = 1036800 xname = lon xlongname = longitude xunits = degrees_east yname = lat ylongname = latitude yunits = degrees_north xsize = 1440 ysize = 720 xfirst = -179.88 xinc = 0.25 yfirst = -89.88 yinc = 0.25
then use CDOs input operator
cdo -f nc -settaxis,2016-04-01,00:00:00,1month -setname,OMIH2CO -input,gridfile.txt OM_outfile.nc < OMIH2CO_Grid_720x1440_201604.dat
BUT your ASCII data file do not contain the 1440x720 (=1036800) input elements!
-Karin
RE: convert .dat file to .nc file - Added by kunal bali over 6 years ago
Thanks for reply,
But the given code is not working. the processed as
Pushps-iMac:amit_kumar_sir Sagnik$ cdo -f nc -settaxis,2016-04-01,00:00:00,1month -setname,OMIH2CO -input,gridfile.txt OM_outfile.nc<OMIH2CO_Grida_720x1440_201604.dat
cdo settaxis: Started child process "setname,OMIH2CO -input,gridfile.txt (pipe1.1)".
cdo(2) setname: Started child process "input,gridfile.txt (pipe2.1)".
cdo(3) input: Enter all 1036800 elements of timestep 1!
cdo(3) input (Abort): Too few input elements (523080 of 1036800)!
Also, The data downloading link is given below
http://h2co.aeronomie.be/ch2o/ch2o.php?period=month&instr=omi&Month=04&Year=2016
RE: convert .dat file to .nc file - Added by Karin Meier-Fleischer over 6 years ago
Yup, the problem are the NaNs they have to be set to a missing value and then everything works fine.
cat OMIH2CO_Grid_720x1440_201604.dat | sed -e 's|NaN|1e20|g' > OMIH2CO_Grid_720x1440_201604_changed.dat
cdo -f nc -settaxis,2016-04-01,00:00:00,1month -setname,OMIH2CO -setmissval,1e20 -input,gridfile.txt OM_outfile.nc < OMIH2CO_Grid_720x1440_201604_changed.dat
-Karin