CDO

Hi Suman,

I'm sorry but with CDO version 1.9.6 I can't reproduce your problem. What is the error message saying?

cdo sinfo MERRA2_100.tavg1_2d_lnd_Nx.19860101.SUB.nc 
   File format : NetCDF4 zip
    -1 : Institut Source   T Steptype Levels Num    Points Num Dtype : Parameter ID
     1 : unknown  unknown  v instant       1   1      4575   1  F32z : -1            
   Grid coordinates :
     1 : lonlat                   : points=4575 (61x75)
                              lon : 63.125 to 100.625 by 0.625 degrees_east
                              lat : 4 to 41 by 0.5 degrees_north
   Vertical coordinates :
     1 : surface                  : levels=1
   Time coordinate :  24 steps
     RefTime =  1986-01-01 00:30:00  Units = minutes  Calendar = standard
  YYYY-MM-DD hh:mm:ss  YYYY-MM-DD hh:mm:ss  YYYY-MM-DD hh:mm:ss  YYYY-MM-DD hh:mm:ss
  1986-01-01 00:30:00  1986-01-01 01:30:00  1986-01-01 02:30:00  1986-01-01 03:30:00
  1986-01-01 04:30:00  1986-01-01 05:30:00  1986-01-01 06:30:00  1986-01-01 07:30:00
  1986-01-01 08:30:00  1986-01-01 09:30:00  1986-01-01 10:30:00  1986-01-01 11:30:00
  1986-01-01 12:30:00  1986-01-01 13:30:00  1986-01-01 14:30:00  1986-01-01 15:30:00
  1986-01-01 16:30:00  1986-01-01 17:30:00  1986-01-01 18:30:00  1986-01-01 19:30:00
  1986-01-01 20:30:00  1986-01-01 21:30:00  1986-01-01 22:30:00  1986-01-01 23:30:00

cdo info MERRA2_100.tavg1_2d_lnd_Nx.19860101.SUB.nc
    -1 :       Date     Time   Level Gridsize    Miss :     Minimum        Mean     Maximum : Parameter ID
     1 : 1986-01-01 00:30:00       0     4575    1430 :      0.0000  1.3969e-06  0.00046777 : -1            
     2 : 1986-01-01 01:30:00       0     4575    1430 :      0.0000  1.5032e-06  0.00046450 : -1            
     3 : 1986-01-01 02:30:00       0     4575    1430 :      0.0000  2.1813e-06  0.00052397 : -1            
     4 : 1986-01-01 03:30:00       0     4575    1430 :      0.0000  4.5357e-06   0.0010417 : -1            
     5 : 1986-01-01 04:30:00       0     4575    1430 :      0.0000  6.1025e-06   0.0016790 : -1            
     6 : 1986-01-01 05:30:00       0     4575    1430 :      0.0000  7.7888e-06   0.0020541 : -1            
     7 : 1986-01-01 06:30:00       0     4575    1430 :      0.0000  8.0395e-06   0.0020196 : -1            
     8 : 1986-01-01 07:30:00       0     4575    1430 :      0.0000  8.1612e-06   0.0020988 : -1            
     9 : 1986-01-01 08:30:00       0     4575    1430 :      0.0000  6.9487e-06   0.0017235 : -1            
    10 : 1986-01-01 09:30:00       0     4575    1430 :      0.0000  5.7969e-06   0.0015402 : -1            
    11 : 1986-01-01 10:30:00       0     4575    1430 :      0.0000  5.6538e-06   0.0015961 : -1            
    12 : 1986-01-01 11:30:00       0     4575    1430 :      0.0000  4.4911e-06  0.00086476 : -1            
    13 : 1986-01-01 12:30:00       0     4575    1430 :      0.0000  3.9501e-06  0.00071304 : -1            
    14 : 1986-01-01 13:30:00       0     4575    1430 :      0.0000  3.6198e-06  0.00064301 : -1            
    15 : 1986-01-01 14:30:00       0     4575    1430 :      0.0000  3.5841e-06  0.00062076 : -1            
    16 : 1986-01-01 15:30:00       0     4575    1430 :      0.0000  3.5528e-06  0.00056854 : -1            
    17 : 1986-01-01 16:30:00       0     4575    1430 :      0.0000  3.4539e-06  0.00050472 : -1            
    18 : 1986-01-01 17:30:00       0     4575    1430 :      0.0000  3.6530e-06  0.00056224 : -1            
    19 : 1986-01-01 18:30:00       0     4575    1430 :      0.0000  3.9743e-06  0.00053403 : -1            
    20 : 1986-01-01 19:30:00       0     4575    1430 :      0.0000  4.3480e-06  0.00068698 : -1            
    21 : 1986-01-01 20:30:00       0     4575    1430 :      0.0000  4.5688e-06  0.00080148 : -1            
    22 : 1986-01-01 21:30:00       0     4575    1430 :      0.0000  4.4840e-06  0.00085098 : -1            
    23 : 1986-01-01 22:30:00       0     4575    1430 :      0.0000  4.3843e-06  0.00084929 : -1            
    24 : 1986-01-01 23:30:00       0     4575    1430 :      0.0000  4.2832e-06  0.00086196 : -1            
cdo info: Processed 109800 values from 1 variable over 24 timesteps [0.01s 24MB]

cdo daymean MERRA2_100.tavg1_2d_lnd_Nx.19860101.SUB.nc o.nc
cdo daymean: Processed 109800 values from 1 variable over 24 timesteps [0.02s 26MB]
[~/Downloads] > cdo info o.nc 
    -1 :       Date     Time   Level Gridsize    Miss :     Minimum        Mean     Maximum : Parameter ID
     1 : 1986-01-01 12:00:00       0     4575    1430 :      0.0000  4.6023e-06  0.00081728 : -1            
cdo info: Processed 4575 values from 1 variable over 1 timestep [0.00s 24MB]

Thank you Karin. I have solved the issue. Its due to mismatch in hdf5 in cygwin environment.

One more question, I have a netcdf file with different regions named as 1,2,3 (regions) and want to get some statistical values like min maximum, count days etc for each region. How can I do this? I have created an exaple region file attached below. U can use this file over the MERRA data that I have attached in our previous discussion. Please let me know if this is possible in cdo or not?

I am using the following code but its giving same value for all regions
cdo zonmean,region.nc,1 MERRA2_100.tavg1_2d_lnd_Nx.19860101.SUB.nc r1.nc
cdo zonmean,region.nc,2 MERRA2_100.tavg1_2d_lnd_Nx.19860101.SUB.nc r2.nc
cdo zonmean,region.nc,3 MERRA2_100.tavg1_2d_lnd_Nx.19860101.SUB.nc r3.nc

Hope to get back from you soon
Best,

I don't know which or what kind of region you are looking for. The region file contains just one region:

cdo sinfo region.nc 
   File format : NetCDF
    -1 : Institut Source   T Steptype Levels Num    Points Num Dtype : Parameter ID
     1 : unknown  unknown  c instant       1   1      4575   1  I8   : -1            
   Grid coordinates :
     1 : lonlat                   : points=4575 (61x75)
                              lon : 63.125 to 100.625 by 0.625 degrees_east
                              lat : 4 to 41 by 0.5 degrees_north
   Vertical coordinates :
     1 : surface                  : levels=1
cdo sinfo: Processed 1 variable [0.00s 22MB]

Please see the map below. I have created a netcdf file "region.nc" containing this data where the number 1-3 demarcate 3 separate regions. They may not be of perfect shape of a square or rectangle. Now I want to extract statistical values as I have described (mean precipitation in region 1-3 or total recipiatation ) where the precipitation data will be same as MERRA data that I have attached earlier. These two files have same resolution and extent. You can plot the region.nc file. have done this in ArcMap

I frequently use OCGIS (https://github.com/NCPP/ocgis) to extract regions from netCDF files. Just generate a polygon shape file and draw your regions. They used to have an example on how to do this, but I can't find it anymore; I can dig out one of my scripts, if you like.

Hi Andy,
Thank you for your suggestion. Yes I have generated a polygon shapefile with 8-12 regions within a single shape file. I am also looking for an example. If you can find out some examples please do share with me. Thank You.