[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
[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

dnf whatprovides "*/mpif90"

yum install openmpi-devel