private double GoldenSection(out string log, double leftBorder, double rightBorder, double accuracy)
{
log = "Метод золотого сечения:\r\n\r\n" +
"Входные данные:\r\n" +
" Левая граница a = " + leftBorder + "\r\n" +
" Правая граница b = " + rightBorder + "\r\n" +
" Точность eps = " + accuracy + "\r\n\r\n" +
"Итерации:\r\n\r\n";
double tau = (-1 + Math.Sqrt(5)) / 2.0;
double x1 = leftBorder + (rightBorder - leftBorder) * tau;
double x2 = rightBorder - (rightBorder - leftBorder) * tau;
double xm = (leftBorder + rightBorder) / 2;
double y1 = FunctionClass.Function1(x1);
double y2 = FunctionClass.Function1(x2);
double ym = FunctionClass.Function1(xm);
log += "a = " + leftBorder + " " + "b = " + rightBorder + " " + "xm = " + xm + " " + "x1 = " + x1 + " " + "x2 = " + x2 + "\r\n";
log += "F(a) = " + FunctionClass.Function1(leftBorder) + " " + "F(b) = " + FunctionClass.Function1(rightBorder) + " " + "F(xm) = " + ym + " " + "F(x1) = " + y1 + " " + "F(x2) = " + y2 + "\r\n\r\n";
int i = 0;
while (Math.Abs(rightBorder - leftBorder) > accuracy)
{
i++;
if ((y1 < y2))
{
log += "# " + i + " y1 < y2\r\n";
leftBorder = x2;
x2 = x1;
x1 = leftBorder + (rightBorder - leftBorder) * tau;
log += "x1 = " + x1 + "\r\n";
log += "x2 = " + x2 + "\r\n";
}
else if ((y1 > y2))
{
log += "# " + i + " y1 > y2\r\n";
rightBorder = x1;
x1 = x2;
x2 = rightBorder - (rightBorder - leftBorder) * tau;
log += "x1 = " + x1 + "\r\n";
log += "x2 = " + x2 + "\r\n";
}
y1 = FunctionClass.Function1(x1);
y2 = FunctionClass.Function1(x2);
xm = (leftBorder + rightBorder) / 2;
ym = FunctionClass.Function1(xm);
log += "# " + i + " " + xm + "\r\n\r\n";
}
return(xm);
}
private double Bisection(out string log, double leftBorder, double rightBorder, double accuracy)
{
log = "Метод половинного деления:\r\n\r\n" +
"Входные данные:\r\n" +
" Левая граница a = " + leftBorder + "\r\n" +
" Правая граница b = " + rightBorder + "\r\n" +
" Точность eps = " + accuracy + "\r\n\r\n" +
"Итерации:\r\n\r\n";
double x1 = leftBorder + (rightBorder - leftBorder) / 4;
double xm = (leftBorder + rightBorder) / 2;
double x2 = rightBorder - (rightBorder - leftBorder) / 4;
double y1 = FunctionClass.Function1(x1);
double ym = FunctionClass.Function1(xm);
double y2 = FunctionClass.Function1(x2);
log += "a = " + leftBorder + " " + "b = " + rightBorder + " " + "xm = " + xm + " " + "x1 = " + x1 + " " + "x2 = " + x2 + "\r\n";
log += "F(a) = " + FunctionClass.Function1(leftBorder) + " " + "F(b) = " + FunctionClass.Function1(rightBorder) + " " + "F(xm) = " + ym + " " + "F(x1) = " + y1 + " " + "F(x2) = " + y2 + "\r\n\r\n";
int i = 0;
while (Math.Abs(rightBorder - leftBorder) > accuracy)
{
i++;
if ((y1 > ym) && (ym < y2))
{
log += "# " + i + " y1 > ym && ym < y2\r\n";
leftBorder = x1;
rightBorder = x2;
log += "a = " + leftBorder + " " + "b = " + rightBorder + "\r\n";
x1 = leftBorder + (rightBorder - leftBorder) / 4;
x2 = rightBorder - (rightBorder - leftBorder) / 4;
log += "x1 = " + x1 + " " + "x2 = " + x2 + "\r\n";
}
else if ((y1 > ym) && (ym > y2))
{
log += "# " + i + " y1 > ym && ym > y2\r\n";
leftBorder = xm;
log += "a = " + leftBorder + "\r\n";
x1 = leftBorder + (rightBorder - leftBorder) / 4;
x2 = rightBorder - (rightBorder - leftBorder) / 4;
xm = (leftBorder + rightBorder) / 2;
log += "x1 = " + x1 + " " + "xm = " + xm + " " + "x2 = " + x2 + "\r\n";
ym = FunctionClass.Function1(xm);
}
else if ((y1 < ym) && (ym < y2))
{
log += "# " + i + " y1 < ym && ym < y2\r\n";
rightBorder = xm;
log += "b = " + rightBorder + "\r\n";
x1 = leftBorder + (rightBorder - leftBorder) / 4;
x2 = rightBorder - (rightBorder - leftBorder) / 4;
xm = (leftBorder + rightBorder) / 2;
log += "x1 = " + x1 + " " + "xm = " + xm + " " + "x2 = " + x2 + "\r\n";
ym = FunctionClass.Function1(xm);
}
y1 = FunctionClass.Function1(x1);
y2 = FunctionClass.Function1(x2);
log += "y1 = " + y1 + " " + "ym = " + ym + " " + "y2 = " + y2 + "\r\n";
log += "xm = " + xm + "\r\n\r\n";
}
return(xm);
}
