我正在尝试弄清楚如何使用 SWIG 包装一个将 2d vector 返回给 python 的 c++ 函数。我有文件 functions.h
#include <vector>
std::vector< std::vector<double> > array_mean(std::vector< std::vector<double> > array)
{
std::vector< std::vector<double> > mean_array( rows, std::vector<double>(cols));
....
return mean_array;
}
在接口(interface)文件functions.i中有
%module functions
%{
#include "functions.h"
%}
%include "std_vector.i"
namespace std {
%template(VecVecdouble) vector< vector<double> >;
}
%include "functions.h"
然后我执行
swig -c++ -python functions.i
g++ -O2 -fPIC -c functions_wrap.cxx -I/usr/include/python2.4 -I/usr/lib/python2.4
然后编译器吐出一堆错误。
functions_wrap.cxx: In function 'bool swig::check(PyObject*) [with Type = double]':
functions_wrap.cxx:3763: instantiated from 'bool swig::PySequence_Cont<T>::check(bool) const [with T = double]'
functions_wrap.cxx:3820: instantiated from 'static int swig::traits_asptr_stdseq<Seq, T>::asptr(PyObject*, Seq**) [with Seq = std::vector<double, std::allocator<double> >, T = double]'
知道问题出在哪里吗？谢谢。
编辑以包含完整的编译器输出
functions_wrap.cxx:3878: instantiated from 'static int
swig::traits_asptr<std::vector<T, std::allocator<_CharT> > >::asptr(PyObject*, std::vector<T, std::allocator<_CharT> >**) [with T = double]'
functions_wrap.cxx:3030: instantiated from 'int swig::asptr(PyObject*, Type**) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3152: instantiated from 'static bool swig::traits_check<Type, swig::pointer_category>::check(PyObject*) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3159: instantiated from 'bool swig::check(PyObject*) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3763: instantiated from 'bool swig::PySequence_Cont<T>::check(bool) const [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3820: instantiated from 'static int swig::traits_asptr_stdseq<Seq, T>::asptr(PyObject*, Seq**) [with Seq = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >, T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3878: instantiated from 'static int swig::traits_asptr<std::vector<T, std::allocator<_CharT> > >::asptr(PyObject*, std::vector<T, std::allocator<_CharT> >**) [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3030: instantiated from 'int swig::asptr(PyObject*, Type**) [with Type = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >]'
functions_wrap.cxx:4946: instantiated from here
functions_wrap.cxx:3159: error: no type named 'category' in 'struct swig::traits<double>'
functions_wrap.cxx: In function 'const char* swig::type_name() [with Type = double]':
functions_wrap.cxx:2946: instantiated from 'static swig_type_info* swig::traits_info<Type>::type_info() [with Type = double]'
functions_wrap.cxx:2953: instantiated from 'swig_type_info* swig::type_info() [with Type = double]'
functions_wrap.cxx:2987: instantiated from 'static PyObject* swig::traits_from_ptr<Type>::from(Type*, int) [with Type = double]'
functions_wrap.cxx:2993: instantiated from 'static PyObject* swig::traits_from<Type>::from(const Type&) [with Type = double]'
functions_wrap.cxx:3005: instantiated from 'PyObject* swig::from(const Type&) [with Type = double]'
functions_wrap.cxx:3862: instantiated from 'static PyObject* swig::traits_from_stdseq<Seq, T>::from(const Seq&) [with Seq = std::vector<double, std::allocator<double> >, T = double]'
functions_wrap.cxx:3885: instantiated from 'static PyObject* swig::traits_from<std::vector<T, std::allocator<_CharT> > >::from(const std::vector<T, std::allocator<_CharT> >&) [with T = double]'
functions_wrap.cxx:3005: instantiated from 'PyObject* swig::from(const Type&) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3862: instantiated from 'static PyObject* swig::traits_from_stdseq<Seq, T>::from(const Seq&) [with Seq = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >, T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3885: instantiated from 'static PyObject* swig::traits_from<std::vector<T, std::allocator<_CharT> > >::from(const std::vector<T, std::allocator<_CharT> >&) [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3005: instantiated from 'PyObject* swig::from(const Type&) [with Type = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >]'
functions_wrap.cxx:6430: instantiated from here
functions_wrap.cxx:2936: error: 'type_name' is not a member of 'swig::traits<double>'
functions_wrap.cxx: In function 'Type swig::as(PyObject*, bool) [with Type = double]':
functions_wrap.cxx:3563: instantiated from 'swig::PySequence_Ref<T>::operator T() const [with T = double]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:285: instantiated from 'static _OI std::__copy<_BoolType, std::random_access_iterator_tag>::copy(_II, _II, _OI) [with _II = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _OI = double*, bool _BoolType = false]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:317: instantiated from '_OI std::__copy_aux(_II, _II, _OI) [with _II = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _OI = double*]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:326: instantiated from 'static _OI std::__copy_normal<<anonymous>, <anonymous> >::copy_n(_II, _II, _OI) [with _II = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _OI = double*, bool <anonymous> = false, bool <anonymous> = false]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:387: instantiated from '_OutputIterator std::copy(_InputIterator, _InputIterator, _OutputIterator) [with _InputIterator = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _OutputIterator = double*]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/vector.tcc:230: instantiated from 'void std::vector<_Tp, _Alloc>::_M_assign_aux(_ForwardIterator, _ForwardIterator, std::forward_iterator_tag) [with _ForwardIterator = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _Tp = double, _Alloc = std::allocator<double>]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_vector.h:853: instantiated from 'void std::vector<_Tp, _Alloc>::_M_assign_dispatch(_InputIterator, _InputIterator, __false_type) [with _InputIterator = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _Tp = double, _Alloc = std::allocator<double>]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_vector.h:319: instantiated from 'void std::vector<_Tp, _Alloc>::assign(_InputIterator, _InputIterator) [with _InputIterator = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _Tp = double, _Alloc = std::allocator<double>]'
functions_wrap.cxx:3801: instantiated from 'void swig::assign(const PySeq&, Seq*) [with PySeq = swig::PySequence_Cont<double>, Seq = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3816: instantiated from 'static int swig::traits_asptr_stdseq<Seq, T>::asptr(PyObject*, Seq**) [with Seq = std::vector<double, std::allocator<double> >, T = double]'
functions_wrap.cxx:3878: instantiated from 'static int swig::traits_asptr<std::vector<T, std::allocator<_CharT> > >::asptr(PyObject*, std::vector<T, std::allocator<_CharT> >**) [with T = double]'
functions_wrap.cxx:3030: instantiated from 'int swig::asptr(PyObject*, Type**) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3152: instantiated from 'static bool swig::traits_check<Type, swig::pointer_category>::check(PyObject*) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3159: instantiated from 'bool swig::check(PyObject*) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3763: instantiated from 'bool swig::PySequence_Cont<T>::check(bool) const [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3820: instantiated from 'static int swig::traits_asptr_stdseq<Seq, T>::asptr(PyObject*, Seq**) [with Seq = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >, T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3878: instantiated from 'static int swig::traits_asptr<std::vector<T, std::allocator<_CharT> > >::asptr(PyObject*, std::vector<T, std::allocator<_CharT> >**) [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3030: instantiated from 'int swig::asptr(PyObject*, Type**) [with Type = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >]'
functions_wrap.cxx:4946: instantiated from here
functions_wrap.cxx:3138: error: no type named 'category' in 'struct swig::traits<double>'
[jdensmor@ls10977 test]$ g++ -O2 -fPIC -c functions_wrap.cxx -I/usr/include/python2.4 -I/usr/lib/python2.4
functions_wrap.cxx: In function 'bool swig::check(PyObject*) [with Type = double]':
functions_wrap.cxx:3763: instantiated from 'bool swig::PySequence_Cont<T>::check(bool) const [with T = double]'
functions_wrap.cxx:3820: instantiated from 'static int swig::traits_asptr_stdseq<Seq, T>::asptr(PyObject*, Seq**) [with Seq = std::vector<double, std::allocator<double> >, T = double]'
functions_wrap.cxx:3878: instantiated from 'static int swig::traits_asptr<std::vector<T, std::allocator<_CharT> > >::asptr(PyObject*, std::vector<T, std::allocator<_CharT> >**) [with T = double]'
functions_wrap.cxx:3030: instantiated from 'int swig::asptr(PyObject*, Type**) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3152: instantiated from 'static bool swig::traits_check<Type, swig::pointer_category>::check(PyObject*) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3159: instantiated from 'bool swig::check(PyObject*) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3763: instantiated from 'bool swig::PySequence_Cont<T>::check(bool) const [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3820: instantiated from 'static int swig::traits_asptr_stdseq<Seq, T>::asptr(PyObject*, Seq**) [with Seq = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >, T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3878: instantiated from 'static int swig::traits_asptr<std::vector<T, std::allocator<_CharT> > >::asptr(PyObject*, std::vector<T, std::allocator<_CharT> >**) [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3030: instantiated from 'int swig::asptr(PyObject*, Type**) [with Type = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >]'
functions_wrap.cxx:4946: instantiated from here
functions_wrap.cxx:3159: error: no type named 'category' in 'struct swig::traits<double>'
functions_wrap.cxx: In function 'const char* swig::type_name() [with Type = double]':
functions_wrap.cxx:2946: instantiated from 'static swig_type_info* swig::traits_info<Type>::type_info() [with Type = double]'
functions_wrap.cxx:2953: instantiated from 'swig_type_info* swig::type_info() [with Type = double]'
functions_wrap.cxx:2987: instantiated from 'static PyObject* swig::traits_from_ptr<Type>::from(Type*, int) [with Type = double]'
functions_wrap.cxx:2993: instantiated from 'static PyObject* swig::traits_from<Type>::from(const Type&) [with Type = double]'
functions_wrap.cxx:3005: instantiated from 'PyObject* swig::from(const Type&) [with Type = double]'
functions_wrap.cxx:3862: instantiated from 'static PyObject* swig::traits_from_stdseq<Seq, T>::from(const Seq&) [with Seq = std::vector<double, std::allocator<double> >, T = double]'
functions_wrap.cxx:3885: instantiated from 'static PyObject* swig::traits_from<std::vector<T, std::allocator<_CharT> > >::from(const std::vector<T, std::allocator<_CharT> >&) [with T = double]'
functions_wrap.cxx:3005: instantiated from 'PyObject* swig::from(const Type&) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3862: instantiated from 'static PyObject* swig::traits_from_stdseq<Seq, T>::from(const Seq&) [with Seq = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >, T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3885: instantiated from 'static PyObject* swig::traits_from<std::vector<T, std::allocator<_CharT> > >::from(const std::vector<T, std::allocator<_CharT> >&) [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3005: instantiated from 'PyObject* swig::from(const Type&) [with Type = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >]'
functions_wrap.cxx:6430: instantiated from here
functions_wrap.cxx:2936: error: 'type_name' is not a member of 'swig::traits<double>'
functions_wrap.cxx: In function 'Type swig::as(PyObject*, bool) [with Type = double]':
functions_wrap.cxx:3563: instantiated from 'swig::PySequence_Ref<T>::operator T() const [with T = double]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:285: instantiated from 'static _OI std::__copy<_BoolType, std::random_access_iterator_tag>::copy(_II, _II, _OI) [with _II = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _OI = double*, bool _BoolType = false]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:317: instantiated from '_OI std::__copy_aux(_II, _II, _OI) [with _II = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _OI = double*]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:326: instantiated from 'static _OI std::__copy_normal<<anonymous>, <anonymous> >::copy_n(_II, _II, _OI) [with _II = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _OI = double*, bool <anonymous> = false, bool <anonymous> = false]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_algobase.h:387: instantiated from '_OutputIterator std::copy(_InputIterator, _InputIterator, _OutputIterator) [with _InputIterator = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _OutputIterator = double*]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/vector.tcc:230: instantiated from 'void std::vector<_Tp, _Alloc>::_M_assign_aux(_ForwardIterator, _ForwardIterator, std::forward_iterator_tag) [with _ForwardIterator = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _Tp = double, _Alloc = std::allocator<double>]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_vector.h:853: instantiated from 'void std::vector<_Tp, _Alloc>::_M_assign_dispatch(_InputIterator, _InputIterator, __false_type) [with _InputIterator = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _Tp = double, _Alloc = std::allocator<double>]'
/usr/lib/gcc/i386-redhat-linux/4.1.2/../../../../include/c++/4.1.2/bits/stl_vector.h:319: instantiated from 'void std::vector<_Tp, _Alloc>::assign(_InputIterator, _InputIterator) [with _InputIterator = swig::PySequence_InputIterator<double, const swig::PySequence_Ref<double> >, _Tp = double, _Alloc = std::allocator<double>]'
functions_wrap.cxx:3801: instantiated from 'void swig::assign(const PySeq&, Seq*) [with PySeq = swig::PySequence_Cont<double>, Seq = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3816: instantiated from 'static int swig::traits_asptr_stdseq<Seq, T>::asptr(PyObject*, Seq**) [with Seq = std::vector<double, std::allocator<double> >, T = double]'
functions_wrap.cxx:3878: instantiated from 'static int swig::traits_asptr<std::vector<T, std::allocator<_CharT> > >::asptr(PyObject*, std::vector<T, std::allocator<_CharT> >**) [with T = double]'
functions_wrap.cxx:3030: instantiated from 'int swig::asptr(PyObject*, Type**) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3152: instantiated from 'static bool swig::traits_check<Type, swig::pointer_category>::check(PyObject*) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3159: instantiated from 'bool swig::check(PyObject*) [with Type = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3763: instantiated from 'bool swig::PySequence_Cont<T>::check(bool) const [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3820: instantiated from 'static int swig::traits_asptr_stdseq<Seq, T>::asptr(PyObject*, Seq**) [with Seq = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >, T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3878: instantiated from 'static int swig::traits_asptr<std::vector<T, std::allocator<_CharT> > >::asptr(PyObject*, std::vector<T, std::allocator<_CharT> >**) [with T = std::vector<double, std::allocator<double> >]'
functions_wrap.cxx:3030: instantiated from 'int swig::asptr(PyObject*, Type**) [with Type = std::vector<std::vector<double, std::allocator<double> >, std::allocator<std::vector<double, std::allocator<double> > > >]'
functions_wrap.cxx:4946: instantiated from here
functions_wrap.cxx:3138: error: no type named 'category' in 'struct swig::traits<double>'
最佳答案
您也未能导出内部 vector 类型。
%module functions
%{
#include "functions.h"
%}
%include "std_vector.i"
namespace std {
%template(VecDouble) vector<double>;
%template(VecVecdouble) vector< vector<double> >;
}
%include "functions.h"
附带说明一下，从 SWIG 生成 -csharp 输出是对您在包装器中创建的类型集的一个很好的健全性检查。如果您不懂 C# 也没关系，只需查看创建的 *.cs 文件的名称即可。任何名为 SWIGTYPE_*.cs 的内容都代表您未包装的类型，以及 future 可能出现的问题。
关于c++ - vector< vector <double>> 与 swig 和 python 的参数，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/5262479/
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我正在为一个项目制作一个简单的shell，我希望像在Bash中一样解析参数字符串。foobar"helloworld"fooz应该变成:["foo","bar","helloworld","fooz"]等等。到目前为止，我一直在使用CSV::parse_line，将列分隔符设置为""和.compact输出。问题是我现在必须选择是要支持单引号还是双引号。CSV不支持超过一个分隔符。Python有一个名为shlex的模块:>>>shlex.split("Test'helloworld'foo")['Test','helloworld','foo']>>>shlex.split('Test"
我不确定传递给方法的对象的类型是否正确。我可能会将一个字符串传递给一个只能处理整数的函数。某种运行时保证怎么样？我看不到比以下更好的选择:defsomeFixNumMangler(input)raise"wrongtype:integerrequired"unlessinput.class==FixNumother_stuffend有更好的选择吗？ 最佳答案 使用Kernel#Integer在使用之前转换输入的方法。当无法以任何合理的方式将输入转换为整数时，它将引发ArgumentError。defmy_method(number)
关闭。这个问题需要detailsorclarity.它目前不接受答案。想改进这个问题吗？通过editingthispost添加细节并澄清问题.关闭8年前。Improvethisquestion在首页我有:汽车:VolvoSaabMercedesAudistatic_pages_spec.rb中的测试代码:it"shouldhavetherightselect"dovisithome_pathit{shouldhave_select('cars',:options=>['volvo','saab','mercedes','audi'])}end响应是rspec./spec/request
两者都可以defsetup(options={})options.reverse_merge:size=>25,:velocity=>10end和defsetup(options={}){:size=>25,:velocity=>10}.merge(options)end在方法的参数中分配默认值。问题是:哪个更好？您更愿意使用哪一个？在性能、代码可读性或其他方面有什么不同吗？编辑:我无意中添加了bang(!)...并不是要询问nobang方法与bang方法之间的区别 最佳答案 我倾向于使用reverse_merge方法:option
我有一个只接受一个参数的方法:defmy_method(number)end如果使用number调用方法，我该如何引发错误？？通常，我如何定义方法参数的条件？比如我想在调用的时候报错:my_method(1) 最佳答案 您可以添加guard在函数的开头，如果参数无效则引发异常。例如:defmy_method(number)failArgumentError,"Inputshouldbegreaterthanorequalto2"ifnumbereputse.messageend#=>Inputshouldbegreaterthano