These are aggregate functions as available on stream views and pipes. Aggregate functions serve the purpose of aggregating data and giving it more eaningfull meaning. They are usually a common feature in any data based environment. In database management, for instance aggregate functions are used where multiple rows are grouped together to form a singe value or to find out more significant meaning, represented by a single value on a set of values.
Aggregate functions are also available on pipes and views in PhixFlow. The following composes a set of available functions: