The documentation of a code is a very important component of the code itself. Maintaining an updated documentation is quite complex if the documentation is separated from the source code. The possibility to integrate the documentation directly in the source is a big help. 

The best choice is to have a single file, Code.f90, that contains  simultaneously the code and the documentation. So if the file is processed by the compiler the application-binary is generated while if the file is processed by a documentation tool the documentation is generated:

Code.f90 => COMPILER => Application

Code.f90 => DOCUMENTATION TOOL => Documentation

On the web there are a lot of programs that makes this stuff but the most part of them don't support fortran. For fortran there are 3 tools that are very powerful and open-sourced:

1) ROBODoc

2) f90doc 

3) f95latex

FortranDOC is the result of a compromise: I need a tool that is simple as f90doc, powerful as Robodoc and in pure fortran language as f95latex. Unluckily FortranDOC is not powerful as Robodoc and it is not simple as f90doc. Despite this, FortranDOC is able to generate an automatic API summary and it is able to produce a nice latex documentation. 

From version 0.3 FortranDOC has a Graphical User Interface!

The program is distribuited under GPL v3.

Please send any comments, suggestions, criticism, or bug reports to: 

stefano.zaghi@gmail.com