>. When using a CPU you might need to install the <https://software.intel.com/content/www/us/en/develop/articles/opencl-drivers.html 
% runtimes> as well. The runtimes, however, might not anymore support your current 
% OS version.
% 
% Alternatively, and especially when using AMD CPUs, <http://portablecl.org/docs/html/install.html 
% POCL> is recommended (<http://portablecl.org/download.html download>). Note 
% that if you use the default installation path, you need to move |/usr/local/etc/OpenCL/vendors/p