This OpenCL package requires at least one OpenCL implementation to be installed in order for OpenCL to work. OpenCL is a royalty-free standard (http://www.khronos.org/opencl/) and there are several implementations based on this standard. Each implementation is usually specific to a brand of a computing device (such as GPU, CPU or accelerator). *** OpenCL IMPLEMENTATIONS *** Most common implementations are (in no particular order): Type: GPU Vendor: NVIDIA URL: http://developer.nvidia.com/opencl Mostly supporting NVIDIA GPUs for computation. The OpenCL package has been successfully tested with "NVIDIA GPU computing SDK" on Linux and depending on the GPU device both single and double-precision is supported. The libraries can be either installed from NVIDIA directly or on very recent Debian and Ubuntu (from the non-free section) via apt-get install nvidia-opencl-dev Type: GPU, CPU Vendor: Apple This OpenCL implementation is part of Mac OS X 10.6 (Snow Leopard) and Max OS X 10.7 (Lion) operating systems. The OpenCL package has been successfully tested with nVidia GPU devices (only single-precision is supported on the devices available to us). The OpenCL framework is part of the OS so no additional libraries need to be installed. Type: GPU, CPU, ACC Vendor: ATI / AMD URL: http://developer.amd.com/zones/OpenCLZone/Pages/default.aspx Mostly supporting AMD (formerly ATI) GPUs and AMD CPUs for computation. Since I don't own any AMD GPUs or CPUs I could not test this implementation. However, Kate Cowles reported success with AMD APP SDK on Ubuntu. Type: CPU, ACC Vendor: Intel URL: http://www.intel.com/go/opencl/ Supports Intel CPUs. Given the ubiquity of Intel CPUs this is a good implementation to install for testing. The OpenCL has been successfully tested with this implementation and RForge.net uses this configuration for checks of the package (both single and double precision is supported). For Debian the installation is fairly simple, download from http://software.intel.com/en-us/articles/download-intel-opencl-sdk/ apt-get install libnuma1 fakeroot alien intel_ocl_sdk_1.1_lnx_64.rpm dpkg -i intel-ocl_1.1-13786_amd64.deb (alternatively rpm2cpio can be used to unpack the rpm directly) *** INSTALLATION *** Once you have an OpenCL implementation installed you can install the OpenCL R package using the regular install.packages() or R CMD INSTALL methods. The OpenCL package assumes the availability of OpenCL headers and OpenCL library at compile time. If you installed the OpenCL implementation in a non-standard location, you may have to set the PKG_CFLAGS and/or PKG_LIBS environment variables accordingly (and possibly LD_LIBRARY_PATH on some unix systems), see R documentation on this. --- DISCLAIMER: Product or corporate names may be trademarks or registered trademarks, and are used only for identification and explanation wihtout intent to infringe.