RE: [Dev-C++] static vector initialization

[Ioannis V. <no...@ho...>]

> -----Original Message-----
> From: dev...@li...=20
> [mailto:dev...@li...] On Behalf=20
> Of Anderson Ilha dos Santos
> Sent: Monday, October 14, 2002 11:11 PM
> To: dev...@li...
> Subject: [Dev-C++] static vector initialization
>=20
>=20
>=20
> Greetings,
>=20
> I have been working on a set of utility functions that I=20
> gruped together on an
> entirely static class. The
> private part of this class has a (static) STL vector=20
> container whose components
> I have had trouble to
> intialize. My class partial listing can be given as below,
>=20
> // file utility.hpp
> class Utility
> {
>         // public interface ...
>=20
>         private:
>             static const int size =3D 10;
>             static vector<double> vec;
> }
>=20
> // file utility.cpp
> #include "Utility.hpp"
>
> const int Utility::size;

Not needed. You could do const int Utility::size=3D10; inside the .hpp
file but you do it in the shorter way anyway (which is equivallent).


> vector<double> Utility::vec( size );
>=20
> the private member 'size' can be directly initialized in the=20
> class body because
> it is a static
> integral value. However, I was unable to intialize the vec=20
> components (vec[0],
> vec[1], etc.) directly
> below the vector<double> vec declaration in the utility.cpp=20
> file, just as I
> would have for the other
> static private members of the class. The only way I have=20
> found to initiliaze
> the vec components was
> to use a new function, say 'void init_vec()', and then initialize the
> components inside this new function.
>=20
> I would like to know whether this is indeed the case or if I=20
> am missing
> something. The init_vec()
> approach seems to be something like a "makeshift"=20
> constructor, and I would
> prefer to be able to
> initialize the container components just as I would have to a=20
> usual static
> member.
>=20
> I will appreciate any advice you guys can give me.

At first i do not think you need a private static vector but anyway. If
you have another vector you can copy it directly:

 vector<double> Utility::vec( othervector );

If you have another container e.g. a built in array you can do:

double darray[]=3D{1,2,3,4,5};
// ...

vector<double> Utility::vec(darray, darray+5*sizeof(*darray));

// sizeof(*darray)=3D=3Dsizeof(darray[0])=3D=3Dsizeof(double);

You can do the same for every other container like list etc.


If you do not want to copy, you have to assign every element explicitly
as you did.


Ioannis

* Ioannis Vranos
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