Multiple versions of PetSc

[Satish Balay]

On Tue, 22 Apr 2008, Amit.Itagi at seagate.com wrote:

> 
> Hi,
> 
> I have a naive question. I have a program that uses a C++, complex version
> of PetSc. I need to run a second program that uses a C, real version of
> PetSc. For the first program, I have defined the PETSC_ARCH and PETSC_DIR
> variables in my .tcshrc . In order to get the second program working, do I
> need to install a second version of PetSc ? How do I separate the
> environment variables ?

You would just install with a different PETSC_ARCH value.

Now at compile time - you can use the correct PETSC_ARCH value with make.

for eg:

./config/configure.py PETSC_ARCH=linux-complex --with-clanguage=cxx --with-scalar-type=complex
make PETSC_ARCH=linux-complex all test
make PETSC_ARCH=linux-complex mycode

./config/configure.py PETSC_ARCH=linux-real
make PETSC_ARCH=linux-real all test
make PETSC_ARCH=linux-real mycode

You can set a default PETSC_ARCH in your .cshrc - but to use the other
build - you change it at command-line to make [as indicated above]

Note: both version can coexist in the same PETSC_DIR.

Satish