public void TestAdditionEquations()
{
string varToken = EquationConversion.GetVariableToken();
string constToken = EquationConversion.GetConstToken();
// test-calculate addition
EquationStruct equation = new EquationStruct("+", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
IntervalStruct[] intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true) };
IntervalStruct range = Solver.FindRange(equation, intervals);
Assert.AreEqual(5, range.GetMinBound());
Assert.AreEqual(9, range.GetMaxBound());
// test-calculate additionconstant
equation = new EquationStruct("+", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "4", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 3, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(6, range.GetMinBound());
Assert.AreEqual(7, range.GetMaxBound());
// unittest-solveradditionleftsidenull
equation = new EquationStruct("+", "", new EquationStruct("/", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)), new EquationStruct(varToken, "x", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", -3, 5, true, true), new IntervalStruct("z", -1, 1, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
}
public void TestReversedBounds()
{
//test-parse domainOrder
IntervalStruct interval = new IntervalStruct("x", 4.0, 3.0, true, true);
Assert.AreEqual(3, interval.GetMinBound());
Assert.AreEqual(4, interval.GetMaxBound());
}
public static string PrintInterval(IntervalStruct interval, bool withVarName)
{
string iv = "";
if (interval.GetMinBound() == interval.GetMaxBound())
{
iv = "CONST: " + interval.GetMinBound();
}
else
{
if (withVarName)
{
iv += interval.GetVariableName() + " = ";
}
if (interval.IsLeftBoundClosed())
{
iv += "[";
}
else
{
iv += "(";
}
if (interval.GetMinBound().ToString().Length > 12)
{
iv += interval.GetMinBound() + ", " + System.Environment.NewLine + " " + interval.GetMaxBound();
}
else
{
iv += interval.GetMinBound() + ", " + interval.GetMaxBound();
}
if (interval.IsRightBoundClosed())
{
iv += "]";
}
else
{
iv += ")";
}
}
return(iv);
}
public void TestSetMaxLowerThanMin()
{
// unittest-intervaldatastructuresetlowmax
IntervalStruct interval = new IntervalStruct("x", 3, 4, true, true);
interval.SetMaxBound(-1);
Assert.AreEqual(-1, interval.GetMinBound());
Assert.AreEqual(3, interval.GetMaxBound());
}
public void TestSetMinHigherThanMax()
{
// unittest-intervaldatastructuresethighmin
IntervalStruct interval = new IntervalStruct("x", 3, 4, true, true);
interval.SetMinBound(5);
Assert.AreEqual(4, interval.GetMinBound());
Assert.AreEqual(5, interval.GetMaxBound());
}
public void TestMultiplicationEquations()
{
string varToken = EquationConversion.GetVariableToken();
string constToken = EquationConversion.GetConstToken();
// test-calculate multiplication1
EquationStruct equation = new EquationStruct("*", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
IntervalStruct[] intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true) };
IntervalStruct range = Solver.FindRange(equation, intervals);
Assert.AreEqual(6, range.GetMinBound());
Assert.AreEqual(20, range.GetMaxBound());
// test-calculate multiplication2
equation = new EquationStruct("*", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -1, 3, true, true), new IntervalStruct("y", -3, 5, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(-9, range.GetMinBound());
Assert.AreEqual(15, range.GetMaxBound());
// test-calculate multiplication3
equation = new EquationStruct("*", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -3, -1, true, true), new IntervalStruct("y", -5, -2, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(2, range.GetMinBound());
Assert.AreEqual(15, range.GetMaxBound());
// unittest-solvermultiplicationleftsidenull
equation = new EquationStruct("*", "", new EquationStruct("/", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)), new EquationStruct(varToken, "x", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", -3, 5, true, true), new IntervalStruct("z", -1, 1, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
}
public void TestSetMethodsSimple()
{
// unittest-intervaldatastructuresetters
IntervalStruct interval = new IntervalStruct("x", 3, 4, false, true);
interval.SetMinBound(2);
interval.SetMaxBound(5);
interval.SetLeftBoundClosed(true);
interval.SetRightBoundClosed(false);
Assert.AreEqual(2, interval.GetMinBound());
Assert.AreEqual(5, interval.GetMaxBound());
Assert.AreEqual(true, interval.IsLeftBoundClosed());
Assert.AreEqual(false, interval.IsRightBoundClosed());
}
public void TestAtomicEquations()
{
string varToken = EquationConversion.GetVariableToken();
string constToken = EquationConversion.GetConstToken();
// unittest-solverconstantfunction
EquationStruct equation = new EquationStruct(constToken, "42", null, null);
IntervalStruct[] intervals = new IntervalStruct[] { };
IntervalStruct range = Solver.FindRange(equation, intervals);
Assert.AreEqual(42, range.GetMinBound());
Assert.AreEqual(42, range.GetMaxBound());
// unittest-solvervariablefunction
equation = new EquationStruct(varToken, "x", null, null);
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 3, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(2, range.GetMinBound());
Assert.AreEqual(3, range.GetMaxBound());
}
public void TestPrecedenceOfOperations()
{
string varToken = EquationConversion.GetVariableToken();
string constToken = EquationConversion.GetConstToken();
// x+y−z == (x+y)−z
EquationStruct equation1 = new EquationStruct("+", "", new EquationStruct(varToken, "x", null, null), new EquationStruct("-", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)));
EquationStruct equation2 = new EquationStruct("+", "", new EquationStruct(varToken, "x", null, null), new EquationStruct("()", "", new EquationStruct("-", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)), null));
IntervalStruct[] intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true), new IntervalStruct("z", 2, 2, true, true) };
IntervalStruct range1 = Solver.FindRange(equation1, intervals);
IntervalStruct range2 = Solver.FindRange(equation2, intervals);
Assert.AreEqual(range1.GetMinBound(), range2.GetMinBound());
Assert.AreEqual(range1.GetMaxBound(), range2.GetMaxBound());
// x∗y/z == (x∗y)/z
equation1 = new EquationStruct("*", "", new EquationStruct(varToken, "x", null, null), new EquationStruct("/", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)));
equation2 = new EquationStruct("/", "", new EquationStruct("()", "", new EquationStruct("*", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null)), null), new EquationStruct(varToken, "z", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true), new IntervalStruct("z", 2, 2, true, true) };
range1 = Solver.FindRange(equation1, intervals);
range2 = Solver.FindRange(equation2, intervals);
Assert.AreEqual(range1.GetMinBound(), range2.GetMinBound());
Assert.AreEqual(range1.GetMaxBound(), range2.GetMaxBound());
// x + y∗z == x + (y∗z)
equation1 = new EquationStruct("+", "", new EquationStruct(varToken, "x", null, null), new EquationStruct("*", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)));
equation2 = new EquationStruct("+", "", new EquationStruct(varToken, "x", null, null), new EquationStruct("()", "", new EquationStruct("*", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)), null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true), new IntervalStruct("z", 2, 2, true, true) };
range1 = Solver.FindRange(equation1, intervals);
range2 = Solver.FindRange(equation2, intervals);
Assert.AreEqual(range1.GetMinBound(), range2.GetMinBound());
Assert.AreEqual(range1.GetMaxBound(), range2.GetMaxBound());
// 2x ∗y == (2x)∗y
equation1 = new EquationStruct("*", "", new EquationStruct(constToken, "2", null, null), new EquationStruct("*", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null)));
equation2 = new EquationStruct("*", "", new EquationStruct("()", "", new EquationStruct("*", "", new EquationStruct(constToken, "2", null, null), new EquationStruct(varToken, "x", null, null)), null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true) };
range1 = Solver.FindRange(equation1, intervals);
range2 = Solver.FindRange(equation2, intervals);
Assert.AreEqual(range1.GetMinBound(), range2.GetMinBound());
Assert.AreEqual(range1.GetMaxBound(), range2.GetMaxBound());
// x2 ∗y == (x2)∗y
equation1 = new EquationStruct("*", "", new EquationStruct(varToken, "x2", null, null), new EquationStruct(varToken, "y", null, null));
equation2 = new EquationStruct("*", "", new EquationStruct("()", "", new EquationStruct(varToken, "x2", null, null), null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x2", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true) };
range1 = Solver.FindRange(equation1, intervals);
range2 = Solver.FindRange(equation2, intervals);
Assert.AreEqual(range1.GetMinBound(), range2.GetMinBound());
Assert.AreEqual(range1.GetMaxBound(), range2.GetMaxBound());
// x∗(y + z)
equation1 = new EquationStruct("*", "", new EquationStruct(varToken, "x", null, null), new EquationStruct("()", "", new EquationStruct("+", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)), null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true), new IntervalStruct("z", 2, 2, true, true) };
range1 = Solver.FindRange(equation1, intervals);
Assert.AreEqual(10, range1.GetMinBound());
Assert.AreEqual(28, range1.GetMaxBound());
}
public void TestExponentEquations()
{
string varToken = EquationConversion.GetVariableToken();
string constToken = EquationConversion.GetConstToken();
// test-calculate intervalAsExponents
EquationStruct equation = new EquationStruct("^", "", new EquationStruct(constToken, "2", null, null), new EquationStruct(varToken, "x", null, null));
IntervalStruct[] intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true) };
IntervalStruct range = Solver.FindRange(equation, intervals);
Assert.AreEqual(4, range.GetMinBound());
Assert.AreEqual(16, range.GetMaxBound());
// test-calculate intervalAsExponentsInvalidBase
equation = new EquationStruct("^", "", new EquationStruct(varToken, "1", null, null), new EquationStruct(constToken, "x", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -4, -2, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
// test-calculate intervalWithExponent1
equation = new EquationStruct("^", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "3", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(8, range.GetMinBound());
Assert.AreEqual(64, range.GetMaxBound());
// test-calculate intervalWithExponent2
equation = new EquationStruct("^", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "2", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(4, range.GetMinBound());
Assert.AreEqual(16, range.GetMaxBound());
// test-calculate intervalWithExponent3
equation = new EquationStruct("^", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "2", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 0, 4, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(0, range.GetMinBound());
Assert.AreEqual(16, range.GetMaxBound());
// test-calculate intervalWithExponent4
equation = new EquationStruct("^", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "2", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -2, 4, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(0, range.GetMinBound());
Assert.AreEqual(16, range.GetMaxBound());
// test-calculate intervalWithExponent5
equation = new EquationStruct("^", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "2", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -4, -2, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(4, range.GetMinBound());
Assert.AreEqual(16, range.GetMaxBound());
// test-calculate intervalWithInvalidExponent1
equation = new EquationStruct("^", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "2.1", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(4, range.GetMinBound());
Assert.AreEqual(16, range.GetMaxBound());
// test-calculate intervalWithInvalidExponent2
equation = new EquationStruct("^", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "-1", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
// test-calculate\_intervalsOnlyExponentiation
equation = new EquationStruct("^", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
// unittest-solverexponentleftsidenull
equation = new EquationStruct("^", "", new EquationStruct("/", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)), new EquationStruct(constToken, "4", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("y", -3, 5, true, true), new IntervalStruct("z", -1, 1, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
}
public void TestDivisionEquations()
{
string varToken = EquationConversion.GetVariableToken();
string constToken = EquationConversion.GetConstToken();
// test-calculate divisionPositiveDivisor1
EquationStruct equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
IntervalStruct[] intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 3, 5, true, true) };
IntervalStruct range = Solver.FindRange(equation, intervals);
Assert.AreEqual(2.0 / 5, range.GetMinBound());
Assert.AreEqual(4.0 / 3, range.GetMaxBound());
// test-calculate divisionPositiveDivisor2
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 0, 4, true, true), new IntervalStruct("y", 3, 5, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(0, range.GetMinBound());
Assert.AreEqual(4.0 / 3, range.GetMaxBound());
// test-calculate divisionPositiveDivisor3
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -1, 4, true, true), new IntervalStruct("y", 3, 5, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(-1.0 / 3, range.GetMinBound());
Assert.AreEqual(4.0 / 3, range.GetMaxBound());
// test-calculate divisionPositiveDivisor4
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -2, -1, true, true), new IntervalStruct("y", 3, 5, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(-2.0 / 3, range.GetMinBound());
Assert.AreEqual(-1.0 / 5, range.GetMaxBound());
// test-calculate divisionPositiveDivisor5
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -2, 0, true, true), new IntervalStruct("y", 3, 5, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(-2.0 / 3, range.GetMinBound());
Assert.AreEqual(0, range.GetMaxBound());
// test-calculate divisionNegativeDivisor1
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", -5, -3, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(4.0 / -3, range.GetMinBound());
Assert.AreEqual(2.0 / -5, range.GetMaxBound());
// test-calculate divisionNegativeDivisor2
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 0, 4, true, true), new IntervalStruct("y", -5, -3, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(4.0 / -3, range.GetMinBound());
Assert.AreEqual(0, range.GetMaxBound());
// test-calculate divisionNegativeDivisor3
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -1, 4, true, true), new IntervalStruct("y", -5, -3, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(4.0 / -3, range.GetMinBound());
Assert.AreEqual(-1.0 / -3, range.GetMaxBound());
// test-calculate divisionNegativeDivisor4
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -2, 0, true, true), new IntervalStruct("y", -5, -3, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(0, range.GetMinBound());
Assert.AreEqual(-2.0 / -3, range.GetMaxBound());
// test-calculate divisionNegativeDivisor5
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -2, -1, true, true), new IntervalStruct("y", -5, -3, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(-1.0 / -5, range.GetMinBound());
Assert.AreEqual(-2.0 / -3, range.GetMaxBound());
// test-calculate divisionbyzero
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(constToken, "0", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
// test-calculate divisionMixedIntervalDivisor
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", -3, 5, true, true), new IntervalStruct("z", -1, 1, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
// test-calculate divisionMixedIntervalDivisorZero1
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", -3, 0, true, true), new IntervalStruct("z", -1, 1, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
// test-calculate divisionMixedIntervalDivisorZero2
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct(varToken, "y", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", 0, 3, true, true), new IntervalStruct("z", -1, 1, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
// test-calculate mixedDivisorComponent
// Ideally, I would like this to return a partial answer
equation = new EquationStruct("/", "", new EquationStruct(varToken, "x", null, null), new EquationStruct("()", "", new EquationStruct("*", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)), null));
intervals = new IntervalStruct[] { new IntervalStruct("x", -2, -1, true, true), new IntervalStruct("y", 3, 5, true, true), new IntervalStruct("z", -1, 1, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
// unittest-solverdivisionleftsidenull
equation = new EquationStruct("/", "", new EquationStruct("/", "", new EquationStruct(varToken, "y", null, null), new EquationStruct(varToken, "z", null, null)), new EquationStruct(varToken, "x", null, null));
intervals = new IntervalStruct[] { new IntervalStruct("x", 2, 4, true, true), new IntervalStruct("y", -3, 5, true, true), new IntervalStruct("z", -1, 1, true, true) };
range = Solver.FindRange(equation, intervals);
Assert.AreEqual(null, range);
}