/// <summary>
/// Calculates aproximation of a integral over a given variable on a given interval.
/// </summary>
/// <param name="variableName">Variable to integrate over.</param>
/// <param name="lowerBound">Lower inclusive boundry.</param>
/// <param name="upperBound">Upper exclusive boundry.</param>
/// <param name="step">The step of the integration.</param>
/// <param name="mode">The mode of integration.</param>
/// <returns></returns>
public double Integrate(string variableName, double lowerBound, double upperBound, double step, IntegrationMode mode)
{
if (lowerBound > upperBound)
{
upperBound = lowerBound;
}
double result = 0;
EquationVariable variable = GetVariable(variableName);
variable.Value = lowerBound;
if (mode == IntegrationMode.Rectangle)
{
while (variable.Value < upperBound)
{
result += Calculate() * step;
variable.Value += step;
}
}
else
{
double val;
while (variable.Value < upperBound)
{
val = Calculate();
variable.Value += step;
result += (Calculate() + val) / 2 * step;
}
}
return(result);
}
/// <summary>
/// Adds a new variable to variable list. Returns false if variable with the same name exists.
/// </summary>
/// <param name="variable">The new variable.</param>
/// <returns></returns>
public bool AddVariable(EquationVariable variable)
{
for (int i = 0; i < variables.Count; i++)
{
if (variables[i].Name == variable.Name)
{
return(false);
}
}
variables.Add(variable);
return(true);
}
