Interfaces

FPL uses Fortran 90 generic interfaces to provide a single procedure name for all type/dimension combinations.

Generic Interfaces

Interface	Specific Procedures	Description
check	checkerror, checktype, checkatt	NetCDF error checking
griddims	griddims{2d,3d,4d}_*	Read grid dimensions
readgrid	readgrid{2d,3d,4d}_*	Read data from NetCDF
writegrid	writegrid{2d,3d,4d}_*	Write data to NetCDF
gengrid	gengrid{2d,3d,4d}_*	Generate grids from bounds
setFillValue	setfvalue{2d,3d,4d}_*	Apply fill-value masking
zonalStats	zonalstats{2d,3d,4d}_*	Zonal statistics
dealloc	dealloc{2d,3d,4d}_*	Deallocate structures

How It Works

The compiler dispatches to the correct implementation based on the type of the argument passed. For example:

type(nc2d_float_llf) :: data2d
type(nc3d_int_lld_ti) :: data3d

! Both calls use the same interface name
call readgrid("file2d.nc", data2d)   ! calls readgrid2d_float_llf
call readgrid("file3d.nc", data3d)   ! calls readgrid3d_int_lld_ti

Specific Procedure Naming

Specific procedures follow the pattern:

{operation}{Dd}_{type}_{coord}[_t{ttype}][_l{ltype}]

For setFillValue and zonalStats, the mask/zone and data types are combined (mask/zone type first):

setfvalue{Dd}_{masktype}{datatype}_{coord}[_t{ttype}][_l{ltype}]
zonalstats{Dd}_{zonetype}{datatype}_{coord}[_t{ttype}][_l{ltype}]

Example Resolutions

Call	Resolves To
call griddims(file, nc2d_byte_llf)	griddims2d_byte_llf
call readgrid(file, nc3d_float_llf_ti)	readgrid3d_float_llf_ti
call writegrid(file, nc4d_double_lld_td_lf)	writegrid4d_double_lld_td_lf
call setFillValue(nc2d_float_llf, nc3d_byte_llf_ti)	setfvalue3d_floatbyte_llf_ti
call zonalStats(nc2d_byte_lld, nc3d_double_lld_ti, ...)	zonalstats3d_bytedouble_lld_ti
call dealloc(nc2d_int_lld)	dealloc2d_int_lld