CDO

Hello,

I've detected that timpctl returns missing values when input data is constant in time.

This is my input netcdf file:

netcdf input {
dimensions:
    time = UNLIMITED ; // (3 currently)
variables:
    int time(time) ;
        time:standard_name = "time" ;
        time:units = "hours since 2023-01-01" ;
    float name(time) ;
        name:_FillValue = -999.f ;
        name:units = "m" ;
data:

 time = 0, 1, 2 ;

 name = 99, 99, 99 ;
}

I've executed timpctl to compute an arbitraty percentile (e.g. p100)

cdo timpctl,100 input.nc -timmin input.nc -timmax input.nc output.nc

This results in a missing value, but I expect to get the maximum value (99.0):

data:

 time = 1 ;

 time_bnds =
  0, 2 ;

 name = _ ;

We try again, this time starting with a non-constant serie:

netcdf input {
dimensions:
    time = UNLIMITED ; // (3 currently)
variables:
    int time(time) ;
        time:standard_name = "time" ;
        time:units = "hours since 2023-01-01" ;
    float name(time) ;
        name:_FillValue = -999.f ;
        name:units = "m" ;
data:

 time = 0, 1, 2 ;

 name = 99, 99.1, 99 ;
}

and now we get the correct result (99.1) as expected:

data:

 time = 1 ;

 time_bnds =
  0, 2 ;

 name = 99.1 ;

Thanks

Pedro