How_To_Use_F2PY.txt

# F2PY
f2py is a tool to allow fortran code to be called in python.
in that way, we can visualize fortran code results.

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Before run:
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f2py is part of numpy library
f2py is automatically installed in mac-mini, but not installed in anaconda
use terminal to run f2py, do not use anaconda

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How to run f2py
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1. open a terminal, write a fortran code (AAA.f90) which is a module (BBB) contains a subroutine (CCC)
2. type in terminal "f2py -c AAA.f90 -m AAA
3. the above command will generate a AAA.so file in same folder where AAA.f90 located
4. import AAA.so as a libray in python code. to do so
    4-1. open bash mode in terminal, by type "bash"
    4-2. open python mode in bash, by type "python"
    4-3. call the AAA.so as a library, by type 
        4-3-1. import numpy as np
        4-3-2. import AAA
        4-3-3. AAA.BBB(input_1, input_2, ... , input_n).  !notice we do not need to put an "output" in the (),but in subroutine we have output in ()
        4-3-4. the result will be shown                   !note that model_file_name.module_name(), not subroutine name

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How to run f2py with module_constants involved
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suppose we have AAA.f90 which need BBB_constant.f90 to run
1.type "gfortran -o BBB_constant.exe BBB_constant.f90", this will generate BBB_constant.mod file
2.type "f2py -c AAA.f90 -m AAA", this will readin BBB_constant.mod, and generate AAA.so file
3.same as above "how to run f2py"