让C ++对象数组迭代在Python [英] Make C++ array of objects iterable in Python

问题描述

我有搜索在网络上并没有获得成功。我包裹在下面的示例code到Python（使用痛饮）：

I have searched on the web and didn't get success. I'm wrapping the sample code below to Python (using SWIG):

class atomo {
public:
    int i;
    atomo(int a) {
        i = a;
    };      
};

class funa {
public:
    atomo *lista[3];

    funa() {
        lista[0] = new atomo(1);
        lista[1] = new atomo(2);
        lista[2] = new atomo(3);
    };
};

但使用命令对应的Python不能遍历或访问 LISTA

>>> test = myModule.funa()
>>> test.lista[0]
      Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
      File "<stdin>", line 6, in __iter__
      TypeError: 'SwigPyObject' object is not subscriptable

>>> for i in test.lista:
>>>     print(i)
      Traceback (most recent call last):
      File "<stdin>", line 1, in <module>
      File "<stdin>", line 6, in __iter__
      TypeError: 'SwigPyObject' object is not subscriptable

我怎样才能让 LISTA 迭代？有使用Python列表而不是C ++数组的方式？

How can I make lista iterable? There is a way to use Python lists instead of C++ arrays?

我的Python版本是3.2，我使用痛饮2.0.4使用g ++ 4.6.1

My Python version is 3.2 and I'm using SWIG 2.0.4 with g++ 4.6.1

感谢

推荐答案

，如果你想使用的从你的问题有点不清楚的std ::矢量或数组自己的类型。

It's a little unclear from your question if you want to use std::vector or an array of your own types.

有关的std ::矢量，给出了一些C ++这样的：

For std::vector, given some C++ like:

#include <vector>
#include <string>

struct foo {
  std::string name;
};

inline std::vector<foo> test() {
  std::vector<foo> ret;
  foo instance;
  instance.name = "one";
  ret.push_back(instance);
  instance.name = "two";
  ret.push_back(instance);
  return ret;
}

您可以用％模板， pyabc.i 和 std_vector.i把它包例如：

%module test

%{
#include "test.h"
%}

%include "pyabc.i"
%include "std_vector.i"

%include "test.h"

%template (FooVector) std::vector<foo>;

这将直观地表现在Python类型。你需要调用痛饮的东西，如：

which will behave intuitively on the Python type. You'll need to call SWIG with something like:

swig -python -c++ -py3 -extranative test.i

如果这个想法是包装一个自定义容器直观表现在Python的身边，我给了一个<一个href=\"http://stackoverflow.com/questions/8776328/swig-interfacing-c-library-to-python-creating-iterable-python-data-type-from/8828454#8828454\">detailed例如的在previous答案。

If the idea is to wrap a "custom" container to behave intuitively on the Python side I gave a detailed example in a previous answer.

这篇关于让C ++对象数组迭代在Python的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！