This package requires an OpenCL implementation to be
installed. 

OpenCL is a royalty-free standard (http://www.khronos.org/opencl/) 
and all the major GPU vendors provide their own implementations of
the standard. 

In order to use this package you need to:

1. Install OpenCL supported GPU drivers
	
If you installed the drivers in the last few years, you do not
need to install new drivers. If you have not or just want to be 
sure, find the latest drivers for your GPU and install them. 

2. Install the OpenCL SDK

NVIDIA: 
	
Install the NVIDIA Toolkit. It can be found here: 
https://developer.nvidia.com/cuda-downloads 

AMD: 

Install the AMD APP SDK. It can be found here: 
http://developer.amd.com/appsdk

3. Set paths to library and include folder

On Unix systems you can probably skip this step. On Windows this
step is mandatory. This can be done in R using the Sys.setenv. 
If possible, run R or RStudio as administrator/superuser. 

LIBRARY PATH: 

This is the location of the OpenCL.lib file. On Windows, the 
default folder for this file when using AMD would be 
C:/Program Files (x86)/AMD APP SDK/3.0/lib/x86_64 on a 64-bit system
or C:/Program Files/AMD APP SDK/3.0/lib/x86 on a 32-bit system. 
If you are using NVIDIA, the default folder on a 64-bit system would be 
C:/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v8.0/lib/x64
while the default folder on a 32-bit system would be
C:/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v8.0/lib/Win32

INCLUDE PATH: 

This is the location of the CL folder that includes CL.h file. On Windows,
the default folder for this file when using AMD would be 
C:/Program Files (x86)/AMD APP SDK/3.0/include
If you are using NVIDIA, the default folder would be 
C:/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v8.0/include


After you have identified both folders run the following commands in R:

Library path: 
Sys.setenv(OPENCL_LIB = "path/to/OpenCL/library/files")
Include path: 
Sys.setenv(OPENCL_INCL = "path/to/OpenCL/include/files")

If you changed the default installation path, change the folder accordingly. 
The folder separator should be "/"" instead of "\"