swig hello world example

!README.md

see python module compiled by SWIG returns wrong result

.gitignore

/_hello*.so
/build/
/hello.py
/hello_wrap.c
/MANIFEST
/dist/

hello.c

#include <stdio.h>
#include "hello.h"

double doublefun(double b){
        printf("c(%g)",b);
        return b+12.5;
}

float floatfun(float b){
        printf("c(%f)",b);
        return b+12.5;
}

int intfun(int b){
        printf("c(%d)",b);
        return b+12;
}

hello.h

double doublefun(double b);
float floatfun(float b);
int intfun(int b);

hello.i

%module hello

%{
#include "hello.h"
%}

%include "hello.h"

Makefile

python=python

all: test_hello

test_hello: test_hello.py _hello.so
	$(python) test_hello.py

_hello.so: setup.py hello_wrap.c hello.h hello.c hello.i
	$(python) setup.py build_ext --inplace

hello.py hello_wrap.c: hello.i
	swig -python -o hello_wrap.c $<

sdist: setup.py hello.py hello_wrap.c
	$(python) setup.py sdist
clean:
	-rm hello.py hello_wrap.c _hello*.so *.pyc MANIFEST
	-rm build/ dist/ __pycache__/ -rf

.PHONY: all test_hello clean sdist

MANIFEST.in

include hello.h
include hello.c
include hello.py
include hello_wrap.c
include setup.py

setup.py

import os
from distutils.core import setup, Extension

ext_module = Extension('_hello',
                       sources=['hello_wrap.c', 'hello.c'],
                       depends=['hello.h'],
                   )

setup (name = 'swig-hello-world-example',
       version = '0.1',
       description = "swig hello world example",
       ext_modules = [ext_module],
       py_modules = ["hello"],
   )

test_hello.py

import hello

print("i: %s" % hello.intfun(2))
print("f: %s" % hello.floatfun(2.3))
print("d: %s" % hello.doublefun(2.3))