private void buttonFindMinAndMax_Click(object sender, EventArgs e)
{
float Lowest = float.MaxValue;
float Highest = float.MinValue;
Equation eq = equations[listBoxEquations.SelectedIndex];
float prevX = eq.FromX;
float step = 100f;
float prevY = eq.GetValueInPoint(prevX);
while (prevX <= eq.ToX)
{
float curX = prevX + 1 / step;
float curY = eq.GetValueInPoint(curX);
if (float.IsNaN(curY))
{
prevX += 1 / step;
continue;
}
if (curY < Lowest)
{
Lowest = curY;
MinFuncPoint = new PointF(curX, Lowest);
}
if (curY > Highest)
{
Highest = curY;
MaxFuncPoint = new PointF(curX, Highest);
}
prevX = curX;
prevY = curY;
}
pictureBoxMainField.Refresh();
MessageBox.Show("Минимальное значение на заданном промежутке\n" + Lowest.ToString("0.00") + "\nМаксимальное значение на заданном промежутке\n" + Highest.ToString("0.00"));
}
private void buttonFuncValueInPoint_Click(object sender, EventArgs e)
{
Equation eq = equations[listBoxEquations.SelectedIndex];
float pointX = float.Parse(textBoxPointX.Text.Replace('.', ','));
if (eq.FromX > pointX || eq.ToX < pointX)
{
MessageBox.Show("Выбранная координата не принадлежит области определения");
return;
}
float valueInPoint = eq.GetValueInPoint(pointX);
if (!float.IsNaN(valueInPoint))
{
SelectedPointOfEquation = new PointF(pointX, valueInPoint);
pictureBoxMainField.Refresh();
MessageBox.Show("Значение функции в точке " + pointX.ToString("0;00") + " = " + valueInPoint.ToString("0"));
}
else
{
MessageBox.Show("Значение функции в точке " + pointX.ToString("0;00") + " " + "не существует");
}
}
