revise the normalization constant: normlaize by the number of active vectors, not by the all possible vectors
bugfix for cache positions
clear unused gradients
check for already cleared gradients
try resolve spurious memory allocation: TODO when more memory allocated, do not consume, but simply wait...
limit the # of allocation
tweaked the memory requirement parameters
shufle data using the better random-number generator
use of karma for potentially faster posterior matrix dumping (TODO: pre-compute compressed-output for contiguous regions...)
dump debug messages to std::cerr with feature-names
try to avoid spurious memory consumption
keep track of the buffer size to determine amount of allocation
better map/reduce for gradients
we do not have to limit the mapper's size, since we will check for emptiness
added non-block option for PBS
perform completely non-block way
enlarged buffer size, since the data is already compressed
revise gradient broadcasting strategy
added erase to prepare for MPI version
added one2many and many2one for one-to-many, many-to-one constrained heuristic