fzn2lp

A converter from FlatZinc into an ASP fact format.

Usage

fzn2lp <FILE>

Download

Binaries for 64bit linux and macOS can be found on the release page.

Compile yourself

Clone the git repository and build:

git clone https://github.com/potassco/fzn2lp.git
cd fzn2lp
cargo build --release

The executables can then be found under ./target/release/

Flatzinc to ASP translation

Predicate declarations

Predicate declarations are represented by facts of form:

predicate(PredicateName).
predicate_parameter(PredicateName, Pos, ParameterName, ParameterType).

In predicates the ParameterType can be either bool, int, float, set_of_int, array(L,int),array(L,set_of_int). The types int and set_of_int can have specializations, either range,(value,Int,value,Int) or set,(value,Int).

For example:

predicate my_pred(int:a, {1,2,3}:a2, 1..11:a3, float:b, bool:c,
               set of int: d, set of {1,2,3}: e, set of 1..11: f,
               array [int] of int:g, array [int] of {1,2,3}:h, array [int] of 1..11:i,
               array [int] of set of int:j);

is represented as:

predicate("my_pred").
predicate_parameter("my_pred",0,"a",int).
predicate_parameter("my_pred",1,"a2",int,set,(value,1)).
predicate_parameter("my_pred",1,"a2",int,set,(value,2)).
predicate_parameter("my_pred",1,"a2",int,set,(value,3)).
predicate_parameter("my_pred",2,"a3",int,range,(value,1,value,11)).
predicate_parameter("my_pred",3,"b",float).
predicate_parameter("my_pred",4,"c",bool).
predicate_parameter("my_pred",5,"d",set_of_int).
predicate_parameter("my_pred",6,"e",set_of_int,set,(value,1)).
predicate_parameter("my_pred",6,"e",set_of_int,set,(value,2)).
predicate_parameter("my_pred",6,"e",set_of_int,set,(value,3)).
predicate_parameter("my_pred",7,"f",set_of_int,range,(value,1,value,11)).
predicate_parameter("my_pred",8,"g",array(int,int)).
predicate_parameter("my_pred",9,"h",array(int,int,set,(value,1))).
predicate_parameter("my_pred",9,"h",array(int,int,set,(value,2))).
predicate_parameter("my_pred",9,"h",array(int,int,set,(value,3))).
predicate_parameter("my_pred",10,"i",array(int,int,range,(value,1,value,11))).
predicate_parameter("my_pred",11,"j",array(int,set_of_int)).

Parameters

Basic parameters are declared by facts of form:

parameter_value(ParameterName, ParameterType, ParameterValue).

Here the ParameterType can be either a basic value, or a complex set, range, array.

Value of basic parameter type (value) are integers, floats, true and false. Values of type range have the form (value,Int,value,Int), values of type array have the form (Pos,Type,Int) and values of type set have the form (value,BasicValue).

For example the parameters:

int : a = 1;
float : b = 1.1;
bool : c = true;
array [1..2] of int : d = [42,23];
array [1..2] of float : e = [42.1,23.0];
set of int: f = 23..42;
array [1..3] of set of int : h = [{42,17},1..5,{}];

are represented as:

parameter_value("a",value,1).
parameter_value("b",value,"1.1").
parameter_value("c",value,true).
parameter_value("d",array,(0,value,42)).
parameter_value("d",array,(1,value,23)).
parameter_value("e",array,(0,value,"42.1")).
parameter_value("e",array,(1,value,"23")).
parameter_value("f",range,(value,23,value,42)).
parameter_value("h",array,(0,set,(value,42))).
parameter_value("h",array,(0,set,(value,17))).
parameter_value("h",array,(1,range,(value,1,value,5))).
parameter_value("h",array,(2,empty_set)).

Variable declarations

Variable declarations are presented by facts of form:

variable_type(VariableName, VariableType).
variable_value(VariableName, Type, Value).

Variable types can be either bool, int, float, set_of_int, array(L,int),array(L,set_of_int). The types int and set_of_int can have specializations, either range,(value,Int,value,Int) or set,(value,Int).

For example the variable declarations:

var int : a1 = 1;
var 1..3 : a2;
var {1,2,3} : a3;
var float : b1 = 1.0;
var 0.5..1.5: b2 = 1.0;
var bool : c = true;
array [1..2] of var int : d = [42,23];
array [1..2] of var float : e = [42.1,23.1];
var set of 17..42: f = {17,23};
var set of {17,23,100}: g = {17,23};
array [1..3] of var set of 17..42: h = [{42,17},23..X,{}];

are represented as:

variable_type("a1",int).
variable_value("a1",value,1).

variable_type("a2",int,range,(value,1,value,3)).

variable_type("a3",int,set,(value,1)).
variable_type("a3",int,set,(value,2)).
variable_type("a3",int,set,(value,3)).

variable_type("b1",float).
variable_value("b1",value,"1").

variable_type("b2",float,(bounds,value,"0.5",value,"1.5")).
variable_value("b2",value,"1").

variable_type("c",bool).
variable_value("c",value,true).

variable_type("d",array(2,int)).
variable_value("d",array,(0,value,42)).
variable_value("d",array,(1,value,23)).

variable_type("e",array(2,float)).
variable_value("e",array,(0,value,"42.1")).
variable_value("e",array,(1,value,"23.1")).

variable_type("f",set_of_int,range,(value,17,value,42)).
variable_value("f",set,(value,17)).
variable_value("f",set,(value,23)).

variable_type("g",set_of_int,set,(value,17)).
variable_type("g",set_of_int,set,(value,23)).
variable_type("g",set_of_int,set,(value,100)).
variable_value("g",set,(value,17)).
variable_value("g",set,(value,23)).

variable_type("h",array(3,set_of_int,range,(value,17,value,42))).
variable_value("h",array,(0,set,(value,42))).
variable_value("h",array,(0,set,(value,17))).
variable_value("h",array,(1,range,(value,23,var,"X"))).
variable_value("h",array,(2,empty_set)).

Constraints

Constraints are presented by facts of form:

constraint(ConstraintId, ConstraintName).
constraint_value(ConstraintId, Pos, Type, Expr).

The expressions in constraints can contain variables var or values value. Complex expressions are array, set and range.

For example the constraint:

constraint my_constraint(42, 42.1, true, a, [42,17,X], {X,34}, 37..48, [{42,17},17..34,{X,Y}]);

is represented as:

constraint(c1,"my_constraint").
constraint_value(c1,0,value,42).
constraint_value(c1,1,value,"42.1").
constraint_value(c1,2,value,true).
constraint_value(c1,3,var,"a").
constraint_value(c1,4,array,(0,value,42)).
constraint_value(c1,4,array,(1,value,17)).
constraint_value(c1,4,array,(2,var,"X")).
constraint_value(c1,5,set,(var,"X")).
constraint_value(c1,5,set,(value,34)).
constraint_value(c1,6,range,(value,37,value,48)).
constraint_value(c1,7,array,(0,set,(value,42))).
constraint_value(c1,7,array,(0,set,(value,17))).
constraint_value(c1,7,array,(1,range,(value,17,value,34))).
constraint_value(c1,7,array,(2,set,(var,"X"))).
constraint_value(c1,7,array,(2,set,(var,"Y"))).

Solve statement

The solve statement is represented by one fact of the following form:

solve(satisfy).
solve(maximize, Type, Expr).
solve(minimize, Type, Expr).

For example:

solve minimize X_24;

is represented as:

solve(minimize,var,"X_24").