private static void local_min_example(double a, double b, Func <double, double> f,
string title)
//****************************************************************************80
//
// Purpose:
//
// local_min_example() tests local_min() on one test function.
//
// Licensing:
//
// This code is distributed under the GNU LGPL license.
//
// Modified:
//
// 30 May 2021
//
// Author:
//
// John Burkardt
//
// Input:
//
// double A, B, the endpoints of the interval.
//
// double F ( double x ), the name of a user-supplied
// function, whose local minimum is being sought.
//
// string TITLE, a title for the problem.
//
{
int calls = 0;
double x = 0;
double t = Math.Sqrt(typeMethods.r8_epsilon());
double fx = LocalMinimum.local_min(a, b, t, f, ref x, ref calls);
double fa = f(a);
double fb = f(b);
Console.WriteLine("");
Console.WriteLine(" " + title + "");
Console.WriteLine("");
Console.WriteLine(" A X B");
Console.WriteLine(" F(A) F(X) F(B)");
Console.WriteLine(" " + a.ToString(CultureInfo.InvariantCulture).PadLeft(14)
+ " " + x.ToString(CultureInfo.InvariantCulture).PadLeft(14)
+ " " + b.ToString(CultureInfo.InvariantCulture).PadLeft(14) + "");
Console.WriteLine(" " + fa
+ " " + fx.ToString(CultureInfo.InvariantCulture).PadLeft(14)
+ " " + fb.ToString(CultureInfo.InvariantCulture).PadLeft(14) + "");
Console.WriteLine(" Number of calls to F = " + calls + "");
}
public void LocalSearchTest()
{
float weigth;
var result = LocalMinimum.LocalSearch(testGraph, out weigth);
var fullCycleWeight = testGraph.CountWeight(testGraph.Vertexes);
Console.WriteLine("Full cycle weight is " + fullCycleWeight);
Console.WriteLine("Locmin cycle weight is " + weigth);
Console.WriteLine("Result cycle vertexies: ");
for (int i = 0; i < result.Count; i++)
{
Console.Write(result[i] + " ");
}
}
public static void test047()
//****************************************************************************80
//
// Purpose:
//
// TEST047 tests MINQUAD.
//
// Licensing:
//
// This code is distributed under the GNU LGPL license.
//
// Modified:
//
// 17 January 2007
//
// Author:
//
// John Burkardt
//
{
double xmin = 0;
double ymin = 0;
Console.WriteLine("");
Console.WriteLine("TEST047");
Console.WriteLine(" MINQUAD finds the minimum of a function");
Console.WriteLine(" F(X) = A * X^2 + B * X + C");
Console.WriteLine(" within an interval, given three data points.");
//
// Case 1: a minimum is in the interval.
// y = ( x - 1 )**2 + 4
//
double x1 = 0.0;
double y1 = (x1 - 1.0) * (x1 - 1.0) + 4.0;
double x2 = 2.0;
double y2 = (x2 - 1.0) * (x2 - 1.0) + 4.0;
double x3 = 3.0;
double y3 = (x3 - 1.0) * (x3 - 1.0) + 4.0;
bool result = LocalMinimum.minquad(x1, y1, x2, y2, x3, y3, ref xmin, ref ymin);
switch (result)
{
case false:
Console.WriteLine("");
Console.WriteLine("Warning");
Console.WriteLine(" MINQUAD returned an error code.");
break;
default:
Console.WriteLine("");
Console.WriteLine(" The minimum lies in the interval.");
Console.WriteLine(" X1, Y1 = " + x1 + " " + y1 + "");
Console.WriteLine(" X2, Y2 = " + x2 + " " + y2 + "");
Console.WriteLine(" X3, Y3 = " + x3 + " " + y3 + "");
Console.WriteLine(" XMIN = " + xmin + " YMIN = " + ymin + "");
break;
}
//
// Case 2: the minimum is to the left of the interval.
// y = ( x - 1 )**2 + 4
//
x1 = 2.0;
y1 = (x1 - 1.0) * (x1 - 1.0) + 4.0;
x2 = 4.0;
y2 = (x2 - 1.0) * (x2 - 1.0) + 4.0;
x3 = 5.0;
y3 = (x3 - 1.0) * (x3 - 1.0) + 4.0;
result = LocalMinimum.minquad(x1, y1, x2, y2, x3, y3, ref xmin, ref ymin);
switch (result)
{
case false:
Console.WriteLine("");
Console.WriteLine("Warning");
Console.WriteLine(" MINQUAD returned an error code.");
break;
default:
Console.WriteLine("");
Console.WriteLine(" The minimum is to the left of the interval");
Console.WriteLine(" X1, Y1 = " + x1 + " " + y1 + "");
Console.WriteLine(" X2, Y2 = " + x2 + " " + y2 + "");
Console.WriteLine(" X3, Y3 = " + x3 + " " + y3 + "");
Console.WriteLine(" XMIN = " + xmin + " YMIN = " + ymin + "");
break;
}
//
// Case 3: the function is flat.
//
x1 = 11.0;
y1 = 6.0;
x2 = 6.0;
y2 = 6.0;
x3 = 2.0;
y3 = 6.0;
result = LocalMinimum.minquad(x1, y1, x2, y2, x3, y3, ref xmin, ref ymin);
switch (result)
{
case false:
Console.WriteLine("");
Console.WriteLine("Warning");
Console.WriteLine(" MINQUAD returned an error code.");
break;
default:
Console.WriteLine("");
Console.WriteLine(" The function is flat.");
Console.WriteLine(" X1, Y1 = " + x1 + " " + y1 + "");
Console.WriteLine(" X2, Y2 = " + x2 + " " + y2 + "");
Console.WriteLine(" X3, Y3 = " + x3 + " " + y3 + "");
Console.WriteLine(" XMIN = " + xmin + " YMIN = " + ymin + "");
break;
}
//
// Case 4: the function has a maximum.
// y = - ( x - 1 )**2 + 4
//
x1 = 0.0;
y1 = -(x1 - 1.0) * (x1 - 1.0) + 4.0;
x2 = 2.0;
y2 = -(x2 - 1.0) * (x2 - 1.0) + 4.0;
x3 = 3.0;
y3 = -(x3 - 1.0) * (x3 - 1.0) + 4.0;
result = LocalMinimum.minquad(x1, y1, x2, y2, x3, y3, ref xmin, ref ymin);
switch (result)
{
case false:
Console.WriteLine("");
Console.WriteLine("Warning");
Console.WriteLine(" MINQUAD returned an error code.");
break;
default:
Console.WriteLine("");
Console.WriteLine(" The function has a maximum.");
Console.WriteLine(" X1, Y1 = " + x1 + " " + y1 + "");
Console.WriteLine(" X2, Y2 = " + x2 + " " + y2 + "");
Console.WriteLine(" X3, Y3 = " + x3 + " " + y3 + "");
Console.WriteLine(" XMIN = " + xmin + " YMIN = " + ymin + "");
break;
}
}
public static void test046()
//****************************************************************************80
//
// Purpose:
//
// TEST046 tests MINABS.
//
// Licensing:
//
// This code is distributed under the GNU LGPL license.
//
// Modified:
//
// 17 July 2005
//
// Author:
//
// John Burkardt
//
{
double xmin = 0;
double ymin = 0;
Console.WriteLine("");
Console.WriteLine("TEST046");
Console.WriteLine(" MINABS finds the minimum of a function");
Console.WriteLine(" F(X) = a * ABS ( X ) + B");
Console.WriteLine(" within an interval, given three data points.");
//
// Case 1: the three points lie on a straight line.
// (XMIN=9,YMIN=2).
//
double x1 = 14.0;
double y1 = 7.0;
double x2 = 9.0;
double y2 = 2.0;
double x3 = 12.0;
double y3 = 5.0;
LocalMinimum.minabs(x1, y1, x2, y2, x3, y3, ref xmin, ref ymin);
Console.WriteLine("");
Console.WriteLine(" The points lie on a straight line.");
Console.WriteLine(" XMIN = " + xmin + " YMIN = " + ymin + "");
//
// Case 2: the three points straddle a minimum.
// (XMIN=7, YMIN=2).
//
x1 = 3.0;
y1 = 6.0;
x2 = 12.0;
y2 = 7.0;
x3 = 9.0;
y3 = 4.0;
LocalMinimum.minabs(x1, y1, x2, y2, x3, y3, ref xmin, ref ymin);
Console.WriteLine("");
Console.WriteLine(" The points straddle a minimum.");
Console.WriteLine(" XMIN = " + xmin + " YMIN = " + ymin + "");
//
// Case 3: the three points straddle a maximum.
// (XMIN=2, YMIN=5).
//
x1 = 11.0;
y1 = 6.0;
x2 = 6.0;
y2 = 9.0;
x3 = 2.0;
y3 = 5.0;
LocalMinimum.minabs(x1, y1, x2, y2, x3, y3, ref xmin, ref ymin);
Console.WriteLine("");
Console.WriteLine(" The points straddle a maximum.");
Console.WriteLine(" XMIN = " + xmin + " YMIN = " + ymin + "");
}
private static void example_test(double a, double b, Func <double, double> f, string title)
//****************************************************************************80
//
// Purpose:
//
// example_test() tests local_min_rc() on one test function.
//
// Licensing:
//
// This code is distributed under the GNU LGPL license.
//
// Modified:
//
// 16 April 2008
//
// Author:
//
// John Burkardt
//
// Input:
//
// double A, B, the endpoints of the interval.
//
// double F ( double x ), the name of a user-supplied
// function, whose local minimum is being sought.
//
// string TITLE, a title for the problem.
//
{
Console.WriteLine("");
Console.WriteLine(" " + title + "");
Console.WriteLine("");
Console.WriteLine(" Step X F(X)");
Console.WriteLine("");
int step = 0;
double arg = a;
double value = f(arg);
Console.WriteLine(" " + step.ToString().PadLeft(4)
+ " " + arg.ToString("0.################").PadLeft(24)
+ " " + value.ToString("0.################").PadLeft(24) + "");
arg = b;
value = f(arg);
Console.WriteLine(" " + step.ToString().PadLeft(4)
+ " " + arg.ToString("0.################").PadLeft(24)
+ " " + value.ToString("0.################").PadLeft(24) + "");
double a2 = a;
double b2 = b;
int status = 0;
LocalMinimum.LocalMinimumData data = new();
for (;;)
{
arg = LocalMinimum.local_min_rc(ref data, ref a2, ref b2, ref status, value);
if (status < 0)
{
Console.WriteLine("");
Console.WriteLine("example_test(): Fatal error!");
Console.WriteLine(" LOCAL_MIN_RC returned negative status.");
break;
}
value = f(arg);
step += 1;
Console.WriteLine(" " + step.ToString().PadLeft(4)
+ " " + arg.ToString("0.################").PadLeft(24)
+ " " + value.ToString("0.################").PadLeft(24) + "");
if (50 < step)
{
Console.WriteLine("");
Console.WriteLine("example_test() - Fatal error!");
Console.WriteLine(" Too many steps!");
break;
}
if (status == 0)
{
break;
}
}
}
