private double SumForIntegralApproximation(MathFunction func, double a, double b, double[] solutions, double[] coefs)
{
double result = 0;
for (int i = 0; i <= powerForCoefCalculation; i++)
{
double x = (a + b) / 2 + (b - a) / 2 * solutions[i];
result += coefs[i] * func.Calculate(x);
}
result *= (b - a) / 2;
return(result);
}
public double Solve(MathFunction func, double a, double b, int n)
{
if (a == b)
{
return(0);
}
if (a > b)
{
double tmp = a; a = b; b = tmp;
}
double result = 0;
double difference = (b - a) / n;
for (int i = 1; i < n; i++)
{
result += func.Calculate(a + difference * i);
}
result += (func.Calculate(a) + func.Calculate(b)) / 2;
result *= difference;
return(result);
}
public double Solve(MathFunction func, double a, double b, int n)
{
if (a == b)
{
return(0);
}
if (a > b)
{
double tmp = a; a = b; b = tmp;
}
double result = 0;
double difference = (b - a) / (2 * n);
for (int k = 1; k < n; k++)
{
result += 4 * func.Calculate(a + difference * (2 * k - 1));
result += 2 * func.Calculate(a + difference * 2 * k);
}
result += 4 * func.Calculate(b - difference) + func.Calculate(a) + func.Calculate(b);
result *= difference / 3;
return(result);
}
public double Solve(MathFunction func, double a, double b, int n)
{
if (a == b)
{
return(0);
}
if (a > b)
{
double tmp = a;
a = b; b = tmp;
}
double result = 0;
double difference = (b - a) / n;
for (int i = 0; i < n; i++)
{
result += func.Calculate(SuitableXForIndex(a + difference * i, a + difference * (i + 1)));
}
result *= difference;
return(result);
}
public GraphicsPath PathForSimpsonMethod(MathFunction func, double a, double b, int n)
{
GraphicsPath path = new GraphicsPath();
double difference = (b - a) / n;
for (int i = 0; i < n; i++)
{
double x = a + difference * i;
MathFunction simpsonFunc = FunctionForSimpsonInterval(new PointF((float)x, (float)func.Calculate(x)),
new PointF((float)(x + difference / 2), (float)func.Calculate(x + difference / 2)),
new PointF((float)(x + difference), (float)func.Calculate(x + difference)));
path.AddPath(PathForFunction(simpsonFunc, x, x + difference), false);
}
return(path);
}
public GraphicsPath PathForFunction(MathFunction func, double a, double b)
{
GraphicsPath path = new GraphicsPath();
path.StartFigure();
path.AddLines(PointsForFunction(func, a, b));
path.AddLine(new PointF((float)FunctionXToScreenX(b), (float)FunctionYToScreenY(func.Calculate(b))),
new PointF((float)FunctionXToScreenX(b), (float)FunctionYToScreenY(0)));
path.AddLine(new PointF((float)FunctionXToScreenX(b), (float)FunctionYToScreenY(0)),
new PointF((float)FunctionXToScreenX(a), (float)FunctionYToScreenY(0)));
path.CloseFigure();
return(path);
}
private PointF[] PointsForFunction(MathFunction func, double a, double b)
{
int count = Convert.ToInt32((b - a) / epsilan) + 1;
PointF[] points = new PointF[Convert.ToInt32((b - a) / epsilan) + 1];
for (int i = 0; i < count; i++)
{
points[i] = new PointF((float)FunctionXToScreenX(a + i * epsilan), (float)FunctionYToScreenY(func.Calculate(a + i * epsilan)));
}
return(points);
}