public static double Solve(Function function, double x)
{
Stack P = new Stack();
double s = 0;
double a, b;
for (int i = 0; i < function.RPNsequence.Length; i++)
{
if (string.IsNullOrEmpty(function.RPNsequence[i])) continue;
else
{
if (char.IsDigit(function.RPNsequence[i][0]))
{
P.Push(function.RPNsequence[i]);
}
else if ((char.IsLetter(function.RPNsequence[i][0])) &&
(function.RPNsequence[i][0] != function.Argument) && (function.RPNsequence[i][0] != '\u03c0') &&
(function.RPNsequence[i][0] != 'e'))
{
double X = Convert.ToDouble(P.Pop());
switch (function.RPNsequence[i])
{
case "sqrt":
P.Push(Math.Sqrt(X));
break;
case "abs":
P.Push(Math.Abs(X));
break;
case "sin":
P.Push(Math.Sin(X));
break;
case "sinh":
P.Push(Math.Sinh(X));
break;
case "cosh":
P.Push(Math.Cosh(X));
break;
case "cos":
P.Push(Math.Cos(X));
break;
case "cth":
P.Push(1 / Math.Tanh(X));
break;
case "tanh":
P.Push(Math.Tanh(X));
break;
case "tan":
P.Push(Math.Tan(X));
break;
case "cot":
P.Push(1 / Math.Tan(X));
break;
case "аbs":
P.Push(Math.Abs(X));
break;
case "ln":
P.Push(Math.Log(X));
break;
case "arsinh":
P.Push(Math.Log(X + Math.Sqrt(X * X + 1)));
break;
case "arcsin":
P.Push(Math.Asin(X));
break;
case "arcosh":
P.Push(Math.Log(X + Math.Sqrt(X + 1) * Math.Sqrt(X - 1)));
break;
case "arccos":
P.Push(Math.Acos(X));
break;
case "artanh":
P.Push(Math.Log((X + 1) / (X - 1)) / 2);
break;
case "arccot":
P.Push(Math.Atan(-1 * X) + Math.PI / 2);
break;
case "arcth":
P.Push(Math.Log((X + 1) / (1 - X)) / 2);
break;
case "arctan":
P.Push(Math.Atan(X));
break;
case "log":
P.Push(Math.Log(Convert.ToDouble(P.Pop()), X));
break;
case "sign":
P.Push(Math.Sign(X));
break;
case "rem":
P.Push(Convert.ToDouble(P.Pop()) % X);
break;
case "sec":
P.Push(1 / Math.Cos(x));
break;
case "csc":
P.Push(1 / Math.Sin(x));
break;
case "arcsec":
P.Push(Math.Acos(1 / X));
break;
case "arccsc":
P.Push(Math.Asin(1 / X));
break;
case "sech":
P.Push(1 / Math.Cosh(x));
break;
case "csch":
P.Push(1 / Math.Sinh(x));
break;
case "arsech":
P.Push(Math.Log(1 / x + Math.Sqrt(1 / x + 1) * Math.Sqrt(1 / x - 1)));
break;
case "arcsch":
P.Push(Math.Log(1 / x + Math.Sqrt(1 / x * x + 1)));
break;
}
}
else
{
if (function.RPNsequence[i][0] == 'e') P.Push(Math.E);
else if (function.RPNsequence[i][0] == '\u03c0') P.Push(Math.PI);
else if (function.RPNsequence[i][0] == function.Argument) P.Push(x);
else
{
b = Convert.ToDouble(P.Pop());
a = Convert.ToDouble(P.Pop());
switch (function.RPNsequence[i][0])
{
///binary operations
case '+':
P.Push(a + b);
break;
case '-':
P.Push(a - b);
break;
case '*':
P.Push(a * b);
break;
case '/':
P.Push(a / b);
s = b;
break;
case '^':
if (b > 1)
{
if ((a < 0) || (a > 0))
{
P.Push(Math.Pow(a, b));
}
else
{
P.Push(0);
}
}
else if ((b < 1) && (b > 0))
{
if (a > 0)
{
P.Push(Math.Pow(a, b));
}
else if (a < 0)
{
if (s % 2 == 1)
{
P.Push(-Math.Pow(Math.Abs(a), b));
}
else P.Push(Math.Pow(a, b));
}
else
{
P.Push(0);
}
}
else if (b == 1)
{
P.Push(a);
}
else if (b == 0)
{
if (a == 0)
{
P.Push(0);
}
else P.Push(1);
}
break;
case ';':
P.Push(b);
P.Push(a);
break;
///unary operations
case '~':
P.Push(a);
P.Push(-1 * Convert.ToDouble(b));
break;
default:
goto y;
}//end switch
}//end else
}
}
}
y: return Convert.ToDouble(P.Pop());
}
private void ConvertToRPN()
{
if (name[0] == '-')
{
name.Remove(0, 1);
name.Insert(0, '~');
}
name.Replace("(-", "(~");
Stack S = new Stack();
RPNsequence = new string[name.Length];
int j = 0;
///Перевод выражения в польскую запись
string function = string.Empty;
int e = 0;
for (; j < name.Length; j++)
{
if ((char.IsDigit(name[j])) || (name[j] == '\u03c0')
|| (name[j] == 'e') || (name[j] == Argument))//в буфере число?
{
RPNsequence[e] += name[j];
if ((j != name.Length - 1) && (!char.IsDigit(name[j + 1]))) e++;
}
else if ((char.IsLetter(name[j])) && (name[j] != Argument) && (name[j] != '\u03c0') && (name[j] != 'e'))
{
while (char.IsLetter(name[j]))
{
function += name[j];
j++;
}
j--;
S.Push(function);
function = string.Empty;
}
else if (name[j] == ';')
{
continue;
}
else
{
if (S.IsEmpty() == true)
{
S.Push(name[j]);
}
else if (GetPriority(Convert.ToString(S.CopyElement())) < GetPriority(name[j].ToString())) //сравнение приоритетов операций
{
S.Push(name[j]);
}
///
else if (name[j] == '(')
{
S.Push(name[j]);
}
else if (name[j] == ')')
{
while (GetPriority(Convert.ToString(S.CopyElement())) != 1)
{
RPNsequence[e] += S.Pop().ToString();
e++;
}
S.DeleteElement();
}
else
{
while (GetPriority(Convert.ToString(S.CopyElement())) >= GetPriority(name[j].ToString()))
{
RPNsequence[e] += S.Pop().ToString();
e++;
}
S.Push(name[j]);
}
}
}
while (S.IsEmpty() != true)
{
e++;
RPNsequence[e] += S.Pop().ToString();
}
}