doubleUnion Function Description

Description

This function takes two or more arguments that are both a bag of double values. It returns a bag of double such that it contains all elements of all the argument bags. The function gets rid of duplicates, as determined by the equality functions.

doubleUnion belongs to the ALFA function reference's Set functions category. It maps to the XACML function identifier urn:oasis:names:tc:xacml:1.0:function:double-union, takes 2 or more arguments and returns a value of type A bag of values of type double with no duplicates..

Property Value
Category Set functions
# Arguments 2 or more
Arguments
  • A bag of type double
  • A bag of type double
  • Optionally more bags of type double
Return Value A bag of values of type double with no duplicates.
Expressed As pre-fix
Representation ALFA short name
Allowed In Target false
ALFA Shorthand None
Commutative true

Example

/**
* Permit if the double 5.0 is in either the first series or the second series
*/
rule doubleUnionExample{
    condition doubleIsIn(5.0,doubleUnion(firstSeries, secondSeries))
    permit
}

In this example, we use the doubleUnion function in conjunction with doubleIsIn to determine whether a single atomic value is in the union of 2 bags of values. This also shows how functions can be combined together in ALFA.

See Also

Related Functions

Other functions in the Set functions category:

Browse the full ALFA function reference.