Feature: Problem as symbolic.Environment interface (#29)

* forced upgrade to main of SymbolicMath

* Upgraded methods for Adding variables + added methods for turning an OptimizationProblem pointer into an Environment

* One more pivot to using the new "Environment" interface features for OP

Author: kwesiRutledge

go.mod

@@ -6,4 +6,4 @@ toolchain go1.23.9
 
 require gonum.org/v1/gonum v0.16.0
 
-require github.com/MatProGo-dev/SymbolicMath.go v0.3.1
+require github.com/MatProGo-dev/SymbolicMath.go v0.3.2-0.20251017032605-a7dee10c22bf

go.sum

@@ -1,4 +1,4 @@
-github.com/MatProGo-dev/SymbolicMath.go v0.3.1 h1:WM5lVAySD4mQDvq3RABUmJgSGkSYHT0CC+ZJXeTTJRg=
-github.com/MatProGo-dev/SymbolicMath.go v0.3.1/go.mod h1:tW8thj4pkaTV9lFNU3OCKmwQ3mZ2Eim6S4JpHRDfRvU=
+github.com/MatProGo-dev/SymbolicMath.go v0.3.2-0.20251017032605-a7dee10c22bf h1:fvHlqO39XHb/TfMm979zsnrcvZDSAFU7PW61g1UQCW8=
+github.com/MatProGo-dev/SymbolicMath.go v0.3.2-0.20251017032605-a7dee10c22bf/go.mod h1:tW8thj4pkaTV9lFNU3OCKmwQ3mZ2Eim6S4JpHRDfRvU=
 gonum.org/v1/gonum v0.16.0 h1:5+ul4Swaf3ESvrOnidPp4GZbzf0mxVQpDCYUQE7OJfk=
 gonum.org/v1/gonum v0.16.0/go.mod h1:fef3am4MQ93R2HHpKnLk4/Tbh/s0+wqD5nfa6Pnwy4E=

problem/optimization_problem.go

@@ -54,11 +54,12 @@ func (op *OptimizationProblem) AddRealVariable() symbolic.Variable {
 func (op *OptimizationProblem) AddVariableClassic(lower, upper float64, vtype symbolic.VarType) symbolic.Variable {
 	id := uint64(len(op.Variables))
 	newVar := symbolic.Variable{
-		ID:    id,
-		Lower: lower,
-		Upper: upper,
-		Type:  vtype,
-		Name:  fmt.Sprintf("x_%v", id),
+		ID:          id,
+		Lower:       lower,
+		Upper:       upper,
+		Type:        vtype,
+		Name:        fmt.Sprintf("x_%v", id),
+		Environment: op,
 	}
 	op.Variables = append(op.Variables, newVar)
 	return newVar
@@ -100,11 +101,12 @@ func (op *OptimizationProblem) AddVariableVectorClassic(
 	vs := make([]symbolic.Variable, num)
 	for i := range vs {
 		vs[i] = symbolic.Variable{
-			ID:    stID + uint64(i),
-			Lower: lower,
-			Upper: upper,
-			Type:  vtype,
-			Name:  fmt.Sprintf("x_%v", stID+uint64(i)),
+			ID:          stID + uint64(i),
+			Lower:       lower,
+			Upper:       upper,
+			Type:        vtype,
+			Name:        fmt.Sprintf("x_%v", stID+uint64(i)),
+			Environment: op,
 		}
 	}
 
@@ -127,14 +129,7 @@ func (op *OptimizationProblem) AddVariableMatrix(
 	// environment as well as upper and lower bounds.
 
 	// Create variables
-	vmOut := symbolic.NewVariableMatrix(rows, cols)
-
-	// Add variables to the problem
-	for i := 0; i < rows; i++ {
-		for j := 0; j < cols; j++ {
-			op.Variables = append(op.Variables, vmOut[i][j])
-		}
-	}
+	vmOut := symbolic.NewVariableMatrix(rows, cols, op)
 
 	return vmOut
 }
@@ -235,10 +230,12 @@ func From(inputModel optim.Model) (*OptimizationProblem, error) {
 	// problem object.
 	for ii, variable := range inputModel.Variables {
 		newOptimProblem.Variables = append(newOptimProblem.Variables, symbolic.Variable{
-			ID:    uint64(ii),
-			Lower: variable.Lower,
-			Upper: variable.Upper,
-			Type:  symbolic.VarType(variable.Vtype),
+			ID:          uint64(ii),
+			Lower:       variable.Lower,
+			Upper:       variable.Upper,
+			Type:        symbolic.VarType(variable.Vtype),
+			Name:        fmt.Sprintf("x_%v", ii),
+			Environment: newOptimProblem,
 		})
 	}
 
@@ -1042,3 +1039,45 @@ func (op *OptimizationProblem) String() string {
 
 	return objString + constraintsString
 }
+
+/*
+GetName
+Description:
+
+	Returns the name of the optimization problem.
+	(Necessary for implementing the symbolic.Environment interface).
+*/
+func (op *OptimizationProblem) GetName() string {
+	return op.Name
+}
+
+/*
+TrackVariable
+Description:
+
+	Adds the given variable to the optimization problem if it is not already present.
+	Returns true if the variable was added, false if it was already present.
+*/
+func (op *OptimizationProblem) TrackVariable(v symbolic.Variable) bool {
+	// Check if the variable is already present
+	for _, variable := range op.Variables {
+		if variable.ID == v.ID {
+			return false
+		}
+	}
+
+	// Add the variable to the problem
+	op.Variables = append(op.Variables, v)
+	return true
+}
+
+/*
+AllTrackedVariables
+Description:
+
+	Returns a slice of all variables that are tracked by the optimization problem.
+	(Necessary for implementing the symbolic.Environment interface).
+*/
+func (op *OptimizationProblem) AllTrackedVariables() []symbolic.Variable {
+	return op.Variables
+}