Statistics: average, median, variance, histogram, etc.

Modules
	mean
	The C++ interface for mean.
	var
	The C++ interface for variance.
	cov
	The C++ interface for covariance.
	stdev
	The C++ interface for standard deviation.
	median
	The C++ interface for median.
	corrcoef
	The C++ interface for Correlation Coefficient.

Detailed Description