Openmpi on Fedora 21 - fedora

Question

I am trying to compile some code in Fedora 21 using 'mpif90'.
First I install openmpi with 'yum':
[root#localhost Inversion]# yum install openmpi
Loaded plugins: langpacks
Package openmpi-1.8.3-2.fc21.x86_64 already installed and latest version
Nothing to do
But then when I compile using 'make' it doesn't work:
[root#localhost Inversion]# make all
mpif90 -O3 -c src/dispersion.f90
make: mpif90: Command not found
Makefile:18: recipe for target 'obj' failed
make: *** [obj] Error 127
As you can see I've downloaded openmpi package but it wont compile.

Answer 1

You cannot compile because you haven't loaded the necessary module.
You need to load the environmental module, this is how Fedora is handling openmpi when you install it using:
dnf install openmpi
(in Fedora 25)
Just follow the following steps:
In your terminal, do:
module avail
You should see an output something like this:
--------------------- /usr/share/Modules/modulefiles ----------------------
dot module-git module-info modules null use.own
---------------------------- /etc/modulefiles -----------------------------
mpi/openmpi-x86_64
Notice there is the mpi/openmpi-x86_64 module available for you to 'load'.
In your terminal, you just do:
module load mpi/openmpi-x86_64
Now you have access to all the mpi compilers like mpif90 and mpic++ etc. You can see that the compiler binaries are stored in: /usr/lib64/openmpi/bin:
$ which mpif90
and you see the output is:
/usr/lib64/openmpi/bin/mpif90

Answer 2

dnf whatprovides "*/mpif90"
tells you what package provides this binary. In Fedora, you can get it from openmpi-devel or mpich packages. So running
yum install openmpi-devel
should do the job for you.