Using F2PY

This page contains a reference to all command-line options for the f2py command, as well as a reference to internal functions of the numpy.f2py module.

Using f2py as a command-line tool

When used as a command-line tool, f2py has three major modes, distinguished by the usage of -c and -h switches.

1. Signature file generation

To scan Fortran sources and generate a signature file, use

f2py -h <filename.pyf> <options> <fortran files>   \
  [[ only: <fortran functions>  : ]                \
    [ skip: <fortran functions>  : ]]...           \
  [<fortran files> ...]

Note

A Fortran source file can contain many routines, and it is often not necessary to allow all routines to be usable from Python. In such cases, either specify which routines should be wrapped (in the only: .. : part) or which routines F2PY should ignore (in the skip: .. : part).

F2PY has no concept of a “per-file” skip or only list, so if functions are listed in only, no other functions will be taken from any other files.

If <filename.pyf> is specified as stdout, then signatures are written to standard output instead of a file.

Among other options (see below), the following can be used in this mode:

--overwrite-signature

Overwrites an existing signature file.

2. Extension module construction

To construct an extension module, use

f2py -m <modulename> <options> <fortran files>   \
  [[ only: <fortran functions>  : ]              \
    [ skip: <fortran functions>  : ]]...          \
  [<fortran files> ...]

The constructed extension module is saved as <modulename>module.c to the current directory.

Here <fortran files> may also contain signature files. Among other options (see below), the following options can be used in this mode: