* MPI examples *

** On Mac **
$ source .env

(be sure you have llvm & libomp installed, path in .env should match it)

** Build **

$ mkdir build && cd build
$ cmake ..
$ make

to build cuda samples configure with
$ cmake .. -DBUILD_CUDA=ON -DCMAKE_CUDA_ARCHITECTURES=<compute_cap>

where compute cap is
$ nvidia-smi --query-gpu=compute_cap --format=csv compute_cap
times 10 (e.g. 5.2 * 10 = 52)

e.g.
$ cmake .. -DBUILD_CUDA=ON -DCMAKE_CUDA_ARCHITECTURES=52

** Run **

$ mpirun -np <num_processes> <file name> 

Example:

$ mpirun -np 4 hello


** Create sample **

create a function and then instantiate the sample as 
SAMPLE(function_name, args)