从C程序中调用Python函数 [英] Call a Python function from within a C program

查看：236 发布时间：2016/10/24 17:20:38 python c++ c python-c-api

本文介绍了从C程序中调用Python函数的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！

问题描述

我在C中有一个应用程序，在某些时候我需要解决一个非线性优化问题。不幸的是，AFAIK有非常有限的资源，在C（请让我知道，否则）。然而，在Python中做它很简单，例如。 scipy.optimize.minimize 。

I have an application in C and at some point I need to solve a non-linear optimization problem. Unfortunately AFAIK there are very limited resources to do that in C (please let me know otherwise). However it is quite simple to do it in Python, e.g. scipy.optimize.minimize.

当我试图这样做时，我遇到了一些似乎很常见的陷阱。 Python.h 未找到，模块未加载，函数调用时出现分段错误等。

While I was trying to do that I encountered some of what it seems to be very frequent pitfalls, e.g. Python.h not found, module not loading, segmentation fault on function call, etc.

推荐答案

有一些事情你必须确保到位以便使此工作：

There are some things that you have to make sure are in place in order to make this work:

确保您已安装Python（您可能需要 python-dev package）。

找到您的 Python.h 文件，例如由找到Python.h 。其中一个应出现在 include 文件夹中的子（子）文件夹中，例如。路径应该是 ../ include / python2.7 / Python.h 。

插入

使用任何教学课程，您都可以在C语言代码中使用#include< path_to_Python.h>调用您的Python函数我使用了这一个，它做了。

Make sure you have Python installed (you may need the python-dev package).
Locate your Python.h file, e.g. by locate Python.h. One of the occurrences should be in a sub(sub)folder in the include folder, e.g. the path should be something like ../include/python2.7/Python.h.
Insert #include "<path_to_Python.h>" in your C code in order to be able to use the Python API.
Use any tutorial to call your Python function. I used this one and it did the trick. However there were a couple of small points missing:

每当你使用任何 Py< Name> 函数，例如 PyImport_Import（），总是检查结果以确保没有错误，例如

Whenever you use any Py<Name> function, e.g. PyImport_Import(), always check the result to make sure there was no error, e.g.

// Load the module object
pModule = PyImport_Import(pName);

if (!pModule)
{
    PyErr_Print();
    printf("ERROR in pModule\n");
    exit(1);
}

在初始化Python解释器之后，即在 Py_Initialize（）; ，您必须将当前路径追加到 sys.path ，以便能够加载模块（假设它位于当前目录中）：

Immediately after initializing the Python interpreter, i.e. after Py_Initialize();, you have to append the current path to sys.path in order to be able to load your module (assuming it is located in your current directory):

PyObject *sys = PyImport_ImportModule("sys");
PyObject *path = PyObject_GetAttrString(sys, "path");
PyList_Append(path, PyString_FromString("."));

记住 ../ include / python2.7 / Python.h 您以前使用过的文件？在文件夹中的 -I 选项中，将 include > gcc 选项，例如 -I /System/Library/Frameworks/Python.framework/Versions/2.7/include 。

还传递到链接器文件夹与所需的库。它应该在 include 文件夹所在的同一文件夹中，例如。 -L /System/Library/Frameworks/Python.framework/Versions/2.7/lib 以及 -lpython2.7 选项（当然根据您的Python版本进行相应调整）。

Remember the ../include/python2.7/Python.h file you used before? Include the include folder in the list of the header files directories with the -I option in the gcc options during compilation, e.g. -I /System/Library/Frameworks/Python.framework/Versions/2.7/include.
Also pass to the linker the folder with the required libraries. It should be inside the same folder where the include folder is located, e.g. -L /System/Library/Frameworks/Python.framework/Versions/2.7/lib, along with the -lpython2.7 option (of course adjusting it accordingly to your Python version).

<现在你必须能够成功地编译和执行你的Python程序调用的C程序。

Now you must be able to successfully compile and execute your C program that calls in it your Python program.

我希望这是有帮助的，祝你好运！

I hope this was helpful and good luck!

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