Full precision output of height levels

Open Discussion
1

The tables A.1 to A.6 of [1] list height levels for zero topography heights. The values are depicted with 3 decimal places. These values should be found in the corresponding HHL and HSURF data files. As the data type of the height values are of type ‘double’ (as shown e.g. by ‘grib_dump’) I expected to find the specific heights dumped with 3 or more decimal places. Unfortunately, these values are printed with 1 decimal place only.

Does this mean, that the internal GRIB2 data, though being of type ‘double’, are stored with a precision of 1 decimal place only? Or must the reason for the shortened output be addressed to ‘grib_dump’ or other corresponding tools?

How can I get access to the full ‘double’ precision of the internal data?

Thanks in advance!

References:
[1] D. Reinert, F. Prill, et.al. - “DWD Database Reference for the Global and Regional ICON and ICON-EPS Forecasting System”, Version 2.5.6

2

grib_dump might be the wrong tool if you want to display a higher precision. Eccodes should also provide grib_get_data which might be more useful in this case, e.g.:

grib_get_data -F "%.4f" input.grib