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Constraint solver that can handle floating point exponentiation

Are there any constraint solvers that can understand exponentiation of potentially unbounded floats aka. real numbers?

Given this simple program,

var float: x;
constraint x^x = 27;
solve satisfy;

I have tried Gecode, HiGHS, COIN-BC, and Chuffed.

Chuffed just doesn't support floats:

Type var float is currently not supported by Chuffed.

The others don't understand the power operator:

Error: solver backend cannot handle constraint: float_pow

Ideally I am looking for a solver with a Zinc frontend, although this is not a must.

Solution

  • JaCoP solver generates the following solution.

    %% WARNING: constraint float_pow is not defined for negative numbers as first argument (decomposition x^y = exp(y*ln(x))); x::{-1.0E150..1.0E150} has minimal value negative (will be pruned).
x = 3.0;
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