• Well-documented: The netCDF Fortran-90 Users Guide is complete and up-to-date.
• Overloaded functions and optional arguments: The Fortran-90 interface is significantly simpler than either the C or Fortran-77 interfaces because of its use of overloaded functions and optional arguments. For example one nf90_put_var() function replaces 30 nf_put_var() functions in the Fortran-77 interface and 40 nc_put_var() functions in the C interface.
• Fewer arguments to functions: string lengths need not be passed for attribute strings, and array lengths need not be passed for dimension arrays. There are fewer and simpler inquiry functions in the Fortran-90 interface with the use of optional arguments.
• Improved error checking: use of intent declarations lets compilers check whether some arguments are used correctly.
• Arbitrary array sections supported: The language allows arbitrary array sections to be passed to any procedure, which may simplify programming.

• Implemented as a thin layer on top of the Fortran-77 library, which in turn is a thin layer on top of the C netCDF-3 library.
• Order of subscripts in CDL: CDL uses row-major order for matrices (last dimension varies fastest), but Fortran uses column-major order (first dimension varies fastest), which can occasionally lead to confusion.
• Not well-tested: Only a few simple tests are run when the netCDF Fortran-90 library is installed.
• No ncgen support: ncgen cannot generate Fortran-90 code, although the Fortran-77 code it generates works from Fortran-90.
• Memory handling: You have to provide memory space for any netCDF data values and attribute values you read.
• Error handling: The status of every function call must be checked, which detracts from code clarity.

Annotated examples of complete Fortran90 netCDF programs are available from the program examples page.

2007 Unidata NetCDF Workshop for Developers and Data Providers > NetCDF APIs