added stream output for std::pair
started histogram classes
first implementation of simplified accumulator design
accumulators: major refactoring
accumulators: added return type inference
accumulators: extended for vector-valued arguments
fixed min(TinyVector,TinyVector) and test
use loop unrolling in min(TinyVector,TinyVector)
accumulators: added merge functionality and test
added operator=(scalar) to various array classes
accumulators: major refactoring of reshape functionality
minor simplification of ScatterMatrix
added CentralMoment and multi-pass functionality (doesn't yet work for vectors)
added pow(TinyVector)
extended CentralMoment
added Skewness and Kurtosis
fixed central moment merge; changed ScatterMatrix => FlatScatterMatrix; added CovarianceEigensystem and test, general refactoring
bit_array: added the possibility to create an empty array
accumulators: refactoring and documentation
accumulators: type list refactoring