Gecode 6.3.0: multiple problems with floats

[matsc-at-sics-se]

var float: x;
var float: y;
constraint x != y;

bash-3.2$ minizinc --solver gecode bugs.mzn 
Error: Registry: Constraint float_lin_ne not found

var -4.9 .. 5.1: x;
var 2..3: r = floor(x);
solve :: float_search([x], 0.01, input_order, indomain_reverse_split) maximize x;
output ["x = \(x), r = \(r);\n"];

bash-3.2$ minizinc --solver gecode bugs.mzn 
x = 4.0, r = 4;

r = 4 is outside the domain.

var -4.9 .. 5.1: x;
var int: r = ceil(x);
solve :: int_search([r], input_order, indomain_max) maximize r;
output ["x = \(x), r = \(r);\n"];

bash-3.2$ minizinc --solver gecode bugs.mzn 
x = 5.0, r = 5;

There is a solution with r = 6.

var -4.9 .. 5.1: x;
var 2..3: r = ceil(x);
solve :: int_search([r], input_order, indomain_min) minimize r;
output ["x = \(x), r = \(r);\n"];

bash-3.2$ minizinc --solver gecode bugs.mzn 
x = 1.0, r = 1;

r = 1 is outside the domain.

var float: a;
var float: b = sin(a);
% var float: b = cos(a);
% var float: b = tan(a);
% var float: b = asin(a);
% var float: b = acos(a);
% var float: b = atan(a);
% var float: b = sinh(a);
% var float: b = cosh(a);
% var float: b = tanh(a);
% var float: b = asinh(a);
% var float: b = acosh(a);
% var float: b = atanh(a);
% var float: b = ln(a);
% var float: b = log2(a);
% var float: b = log10(a);
% var float: b = exp(a);
% var float: b = pow(a,2.0);

bash-3.2$ minizinc --solver gecode bugs.mzn 
Error: Registry: Constraint float_sin not found

and similarly for all the other transcendentals.

[zayenz]

For the transcendentals, it depends on if Gecode is compiled with MPFR-support or not, and it appears that this is not included in the included version of Gecode. This can be checked by running fzn-gecode with the help flag.

$ X /Applications/MiniZincIDE.app/Contents/Resources/bin/fzn-gecode --help
Gecode FlatZinc interpreter
 - Supported FlatZinc version: 1.6

Gecode configuration information:
 - Version: 6.3.0
 - Variable types: BoolVar IntVar SetVar FloatVar 
 - Trigonometric and transcendental float constraints: disabled
 - Thread support: enabled (10 processing units)
 - Gist support: enabled
 - CPProfiler support: enabled
...

Will check on the erroneous cases. On initial inspection I am unclear on how the translation into FlatZinc is done.

[SYury]

Found another case when Gecode has problems with floats. On the example from the docs it prints "UNSATISFIABLE" while CBC finds the solution (I'm using version 2.8.4)