Summary functions

These functions calculate scalar summaries of values in any numerical structure:

`SUM`	Arithmetic sum
`TOTAL`	Synonym for SUM
`MEAN`	Average
`MEDIAN`	Median value
`MINIMUM`	Minimum value
`MAXIMUM`	Maximum value
`MINPOSITION`	Position of minimum value
`MAXPOSITION`	Position of maximum value
`RANGE`	Range of values
`CORRELATION`	Correlation
`COVARIANCE`	Covariance
`SD`	Standard deviation
`SEMEAN`	Standard error of the mean
`SKEWNESS`	Skewness
`KURTOSIS`	Kurtosis
`VARIANCE`	Variance
`NVALUES`	Number of values
`NVRESTRICTED`	Synonym of `NVALUES`
`NVUNRESTRICTED`	number of values ignoring restrictions (i.e. full length)
`NOBSERVATIONS`	Number of observations (non-missing values)
`NMV`	Number of missing values

These functions provide percentiles, quartiles and ranks of the values in any numerical structure:

These functions provide summaries of running sequences of values in a variate:

`RMEANS`	Running means
`RNOBSERVATIONS`	Number of observations contributing to the computation of a running mean or total about each unit
`RTOTALS`	Running totals
`RUNS`	Length of run of identical values up to each unit

These functions give information about the levels of a factor:

`NLEVELS`	Number of levels of a factor
`LEVELS`	Forms a variate containing the levels of the factor

This function gives the Genstat type number of a data structure:

TYPE Type number of a data structure

These functions evaluate areas:

`AREA`	Estimates the area under a curve
`PAREA`	Area of a polygon

These functions indicate whether or not a dummy structure has been set:

`SET`	Returns 1 if a dummy is set, otherwise 0
`UNSET`	Returns 1 if a dummy is unset, otherwise 0

Updated on January 12, 2022