[Trilinos-Users] Outdated example IfpackBelos2; status / replacement of RCP / rcp

[Hoemmen, Mark]

On 6/10/17, 8:34 AM, "Trilinos-Users on behalf of trilinos-users-request at trilinos.org" <trilinos-users-bounces at trilinos.org on behalf of trilinos-users-request at trilinos.org> wrote:
> Date: Fri, 9 Jun 2017 13:33:11 +0200
> From: Joachim Wuttke <j.wuttke at fz-juelich.de>
> To: <trilinos-users at trilinos.org>
> Subject: [Trilinos-Users] Outdated example IfpackBelos2; status / replacement of RCP / rcp
>
> Struggling to learn enough of Trilinos to solve
> a sparse matrix system, I came across the sample code
>
> https://github.com/trilinos/Trilinos_tutorial/wiki/IfpackBelos2
>
> which seemed to me a good starting point. However,
> analysing it line by line, I found that it depends
> on a deprecated function, namely Teuchos::rcp.

It's likely a deprecated overload of Teuchos::rcp.  Most overloads of Teuchos::rcp should not be deprecated.

Please post a GitHub issue with the warning in question:

https://github.com/trilinos/Trilinos/issues/

> - Is there a more up-to-date, simple example to 
>   get me started with solving a sparse matrix system
>   using ILU(0) and GMRES?

That's the example.  See also the MueLu tutorial for more interesting preconditioners.

> - How to replace Teuchos::rcp in constructing RCP objects?

You don't have to.  Please go to Trilinos' GitHub page and post an issue there with the code that reports a deprecated warning, and we'll show you how to fix it.

> - Why not replace RCP by C++11 standard smart pointers?

1. Trilinos did not require C++11 for packages downstream of Kokkos and Tpetra until 2014.
2. Trilinos did not and still does not require Boost.  It's an optional TPL.
3. There are still many Trilinos packages that must build with a C++98 compiler.

mfh