public QuadraticEquation(Equation equation) : base(equation.LeftSide, equation.RightSide)
{
VariableIdentifierCollection resultingVariable;
SolvableEquationFunctions.CheckIfValid(this, 1, 2, new[] { 2d }, out resultingVariable);
ResultingVariable = resultingVariable;
}
internal static void CheckIfValid(Equation equation, double minExponent, double maxExponent, double[] neededExponents, out VariableIdentifierCollection resultingVariable)
{
equation.SimpleSolveForZero();
VariableCollection LeftSide = equation.GetLeftSide();
VariableIdentifierCollection?defaultIdentifiers = null;
foreach (var ii in LeftSide)
{
if (ii.Identifiers.Count > 0)
{
defaultIdentifiers = ii.Identifiers;
break;
}
}
if (!defaultIdentifiers.HasValue)
{
if (LeftSide[0].Multiplier != 0)
{
throw new NoSolutionException();
}
throw new InfinitlyManySolutionsException();
}
bool[] foundExponents = new bool[neededExponents.Length];
foreach (Variable variable in LeftSide)
{
VariableIdentifierCollection identifiers = variable.Identifiers;
if (identifiers.ContainsMarker('i'))
{
throw new NotImplementedException("Cannot solve equations with imaginary numbers in them!");
}
for (int i = 0; i < identifiers.Count; i++)
{
if (!(identifiers.HasSameMarkersAs(defaultIdentifiers.Value) || identifiers.Count == 0))
{
throw new ArgumentException("Inputted equation isn't a solvable equation (there are two or more different variables)!");
}
double[] exponents = identifiers.GetExponents();
for (int j = 1; j < exponents.Length; j++)
{
if (exponents[j] != exponents[j - 1])
{
throw new ArgumentException($"Inputted equation isn't a solvable equation (two or more different exponents in one term)!");
}
}
if (exponents[0] > maxExponent || exponents[0] < minExponent)
{
throw new ArgumentException($"Inputted equation isn't a required type equation (one or more terms have wrong exponent)!");
}
int exponentIndex = Array.IndexOf(neededExponents, exponents[0]);
if (exponentIndex >= 0)
{
foundExponents[exponentIndex] = true;
}
}
}
if (!foundExponents.All(x => x))
{
throw new ArgumentException("Inputted equation doesn't meet necessary requirements (doesn't have all expected exponents)!");
}
VariableIdentifier[] solvableIdentifiers = new VariableIdentifier[defaultIdentifiers.Value.Count];
for (int i = 0; i < solvableIdentifiers.Length; i++)
{
solvableIdentifiers[i] = new VariableIdentifier(defaultIdentifiers.Value[i].Marker, 1);
}
resultingVariable = new VariableIdentifierCollection(solvableIdentifiers);
}
public void SolveFor(VariableIdentifierCollection resultVariable)
{
SimpleSolveForZero();
bool foundResultingVariable = false;
VariableCollection _rightSide = new VariableCollection();
foreach (Variable variable in LeftSide)
{
int matchingVariableCount = 0;
foreach (VariableIdentifier varIdentifier in variable.Identifiers)
{
if (resultVariable.Contains(varIdentifier))
{
matchingVariableCount++;
}
}
if (matchingVariableCount == 0)
{
continue;
}
if (matchingVariableCount == resultVariable.Count)
{
_rightSide.Add(variable);
foundResultingVariable = true;
continue;
}
throw new InvalidOperationException("Cannot solve this equation, beacuse ResultingVariable isn't a single variable in this context!");
}
if (LeftSide.Count == 0 || (LeftSide.Count == 1 && LeftSide[0].Multiplier == 0))
{
throw new InfinitlyManySolutionsException();
}
if (!foundResultingVariable)
{
throw new NoSolutionException("The equation has no solution for the following variable: " + resultVariable);
}
LeftSide -= _rightSide;
RightSide = -(_rightSide);
SimplifyBothSides();
Variable finalVariable = new Variable(resultVariable, 1);
int rightTermsCount = RightSide.Count;
foreach (Variable variable in RightSide)
{
Variable divider = variable / finalVariable;
LeftSide /= divider;
}
LeftSide /= rightTermsCount;
RightSide = finalVariable;
LeftSide.Simplify();
VariableCollection leftSideTmp = LeftSide.Clone();
LeftSide = RightSide;
RightSide = leftSideTmp;
}
