L0 resolutions with repeating decimals
- MERIT DEM is at 3 arc seconds i.e. 0 deg 0 min 3 secs OR 0.00083333.....33333…..
- I use ASCII input format. All of input .asc files and header.txt have the L0 resolution in decimal degrees.
- I noticed that in order to avoid truncation errors the user needs to enter a lot of decimal places in the .asc files and header.txt. E.g. 18 decimal places were not enough. So I entered 100 decimal places - worked. (note: the error occurs at lines 546-547 of mo_grid.f90, calculation of xllcorner and yllcorner from L0 and L2 resolutions)
- In mHM we have two coordinate systems - metric and lat lon. The latter has numeral format of decimal degrees. However, data which come as deg-min-sec when converted to decimal degrees could bear “repeating decimals” leading to truncation errors as in case of MERIT DEM resolution.
- Wouldn’t it be better if users had the option to enter the resolution in deg-min-sec or decimal degrees as deemed fit? That would be more elegant/ intuitive than entering a lot of decimal places.
- I don’t have experience in using .nc files for L0 data (except lai.nc). Does that solve this issue already?
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information