Subset functions

Subsets of elements can be specified with the RESTRICT directive; alternatively, subsets can be copied to new structures using the EQUATE directive. These functions deal with subsets of values.


EXPAND
Forms a logical variate indicating selected units from a variate of unit numbers

NEXPAND
Expand variate by replicating its values

POSITION
Finds the positions of values within any vector

UNIQUE
Forms unique set of values in a numerical data structure

WHERE
Forms set of units in a variate containing non-zero values

RESTRICTION
Forms a logical variate indicating currently restricted units of a vector


In expressions, subsets of structure values can be referred to by qualified identifiers, or by the function:


ELEMENTS
Selects values of any structure