There is no product use nvidia graphic card now(2015.12).
So apple's computer can not use cuda library.
Many machine learning related library use CUDA. cuDNN, cuBlas..
Now I use MAC book pro 2014 retina 15'' that embedded geforce gt 750m.
But I have to concern whether I buy apple notebook or not for next notebook.
I like apple products. but for my study, I need nvidia graphic card for using cuda.