py2f

Allows embedding python code inside fortran.

Installation

make

Using

All functions return an int error code, check against the SUCCESS constant.

Startup

   res=setup()
   if(res/=SUCCESS) THEN
      write(*,*) "Init failed"
      stop
   end if

Initializes the code and must be called before any other py2f function

End

res=finish()

Shutdown python at the end, not much to do if it fails

Set a variable

res=set(str object, str name, int|double|str value)

Creates a parameter called name with value value. If you want to create the variable in the top level python name space ie if you typed

x=1

in the python interpreter, then object=MAIN_MOD,

res=set(MAIN_MOD,"x",1)

otherwise pass the name of the python object as a string.

Can also pass an array of upto 5d of ints or doubles to the set function, note we pass a pointer tp the array, thus if the array ceases to exists (delalocate, exits functions etc) you can't then use it in python.

Get a variable

res=get(str object, str name, int|double|str value)

Gets a parameter called name with value value. If the variable is in the top level python name space, then object=MAIN_MOD, otherwise pass the name of the python object as a string.

You can also pass a 1d allocatable array or a 1d pointer to get (of type int or double). The array version returns a copy while the pointer version is a pointer.

Run command

res=run_cmd(str cmd)

Where cmd is the command to run, for instance

res=run_cmd("x=1")

Import module

res=run_cmd("import numpy as np")

Multiline blocks

res=run_cmd("x=1;y=1")

Use a semi-colon to split commands in one string

res=run_cmd("if x: print x")

Use colon (as normal python), though you can't nest another statement that needs a colon (say nested if statements). For more complicated code, like a function, then put that it in a file and import it.

Accessing sub-objects

Sometimes accessing objects thats are part of other objects wont work using the get command. Instead use:

res=run_cmd("temp=x.a.b")
res=get(MAIN_MOD,"temp",x)

i.e. create a local varaible in the top level namespace and access that

and similairly setting a nested object

res=set(MAIN_MOD,"temp",x)
res=run_cmd("x.a.b=temp")

rjfarmer / py2f