`min`

It calculates the minimum value for one ore more positions on an atom, grouping by the other positions.

The syntax is the following:

@post("atomName","min(p1, ..., pn)").

where atomName is the atom at hand, p1, …, pn are integers denoting a valid position in atomName (starting from 1).

Example 40

t(1,"b",5).
t(1,"b",1).
t(1,"c",1).
p(X,Y,Z) :- t(X,Y,Z).
@output("p").
@post("p","min(3)").

The expected result is:

` p(1,"b",1). p(1,"c",1). `

Note that the min value is computed according to the lexicographic order over tuples obtained by projecting on the positions in the post-processing annotation.

Example

t(1,"b",1).
t(2,"c",1).
t(1,"a",1).
q(X,Y,Z) :- t(X,Y,Z).
@output("q").
@post("q","min(1,2)").

Then the expected result is ` p(1,"a",1). ` Indeed, all the three tuples (1,"b"), (2,"c") and (1,"a") fall within one group, and (1,"a") is a minimal tuple among them according to the lexicographic order.