Adding NetCDF Input/Output File Options

[drnimbusrain]

Adding namelist controlled NetCDF input/output file options for improved assessment and testing of canopy-app modules.

Could also make a netcdf_io module based on NACC to read netcdf inputs: https://github.com/noaa-oar-arl/NACC/blob/master/parallel/src/netcdf_io_mod.f90
canopy_netcdf_io_mod.F90
canopy_outncf.F90

After Issue #22 is completed, the output creation could be moved to txt and netcdf output modules:
canopy_outncf_mod.F90: Based on NACC: https://github.com/noaa-oar-arl/NACC/blob/master/parallel/src/outncf.f90
canopy_outtxt_mod.F90: https://github.com/noaa-oar-arl/canopy-app/blob/develop/canopy_driver.F90#L333

For the input option, we need example input NetCDF file from Issue #25 first. Hopefully, @angehung5 can help generate one based on the current input_variables.txt file.

@zmoon
@drnimbusrain

[drnimbusrain]

@zmoon One thing to consider is that with NetCDF IO we will have to compile model with netcdf-fortran libraries.

[zmoon]

@zmoon One thing to consider is that with NetCDF IO we will have to compile model with netcdf-fortran libraries.

Yes there is that. I do think it would be valuable to keep at least maybe a single-column text input option that doesn't require netCDF. That way simple testing/experimentation can be done without needing to edit netCDF files.

[drnimbusrain]

@zmoon Yes, my thought too.

I hope this could be done by compiling with netcdf-fortran as an option (for when user wants to input and/or output NetCDF) rather than requirement. I think we should keep the text file option, and add two new namelist options (e.g., infile_fmt and outfile_fmt) to namelist.

I also assume we need logic in the Makefile to compile different input (e.g., canopy_intxt_mod.F90 or canopy_inncf_mod.F90) and output submodules (e.g., canopy_outtxt_mod.F90 or canopy_outncf_mod.F90) depending on if the user has selected "netcdf" during compliation, because the NetCDF read/write submodules will have embedded use netcdf-fortran in them.

[zmoon]

Yeah we should be able to do that similar to the current DEBUG option, with conditionals and appending to OBJS. At some point we can move to CMake.

[drnimbusrain]

@zmoon @angehung5 Closing this issue.