### 22.3 Current Statistics

Function: double gsl_rstat_min (gsl_rstat_workspace * w)

This function returns the minimum value added to the accumulator.

Function: double gsl_rstat_max (gsl_rstat_workspace * w)

This function returns the maximum value added to the accumulator.

Function: double gsl_rstat_mean (gsl_rstat_workspace * w)

This function returns the mean of all data added to the accumulator, defined as

\Hat\mu = (1/N) \sum x_i

Function: double gsl_rstat_variance (gsl_rstat_workspace * w)

This function returns the variance of all data added to the accumulator, defined as

\Hat\sigma^2 = (1/(N-1)) \sum (x_i - \Hat\mu)^2

Function: double gsl_rstat_sd (gsl_rstat_workspace * w)

This function returns the standard deviation of all data added to the accumulator, defined as the square root of the variance given above.

Function: double gsl_rstat_sd_mean (gsl_rstat_workspace * w)

This function returns the standard deviation of the mean, defined as

sd_mean = \Hat\sigma / \sqrt{N}

Function: double gsl_rstat_rms (gsl_rstat_workspace * w)

This function returns the root mean square of all data added to the accumulator, defined as

rms = \sqrt ( 1/N \sum x_i^2 )

Function: double gsl_rstat_skew (gsl_rstat_workspace * w)

This function returns the skewness of all data added to the accumulator, defined as

skew = (1/N) \sum ((x_i - \Hat\mu)/\Hat\sigma)^3

Function: double gsl_rstat_kurtosis (gsl_rstat_workspace * w)

This function returns the kurtosis of all data added to the accumulator, defined as

kurtosis = ((1/N) \sum ((x_i - \Hat\mu)/\Hat\sigma)^4)  - 3

Function: double gsl_rstat_median (gsl_rstat_workspace * w)

This function returns an estimate of the median of the data added to the accumulator.