/// <summary>
/// Convecs an infix string to a post fix string.
/// </summary>
/// <remarks><pre>
/// 2004-07-19 - Jeremy Roberts
/// </pre></remarks>
/// <param name="func">The function to convert</param>
/// <returns>A post fix string.</returns>
protected string Infix2Postfix(string func)
{
func = new InfixExpression(func).Expression;
string[] inFix = func.Split(new[] { ' ' });
var postFix = new Stack <string>();
var operators = new Stack <string>();
string currOperator;
foreach (string token in inFix)
{
if (ExpressionKeywords.IsOperand(token))
{
postFix.Push(token);
}
else if (ExpressionKeywords.OpenGroupOperators.Contains(token))
{
operators.Push(token);
}
else if (ExpressionKeywords.ClosingGroupOperators.Contains(token))
{
Grouping g = ExpressionKeywords.GetGroupingFromClose(token);
currOperator = operators.Pop();
while (currOperator != g.Open)
{
postFix.Push(currOperator);
currOperator = operators.Pop();
}
}
else if (ExpressionKeywords.IsOperator(token))
{
// while precedence of the operator is <= precedence of the token
while (operators.Count > 0)
{
if (ExpressionKeywords.GetPrecedence(token) <= ExpressionKeywords.GetPrecedence(operators.Peek()))
{
currOperator = operators.Pop();
postFix.Push(currOperator);
}
else
{
break;
}
}
operators.Push(token);
}
}
while (operators.Count > 0)
{
currOperator = operators.Pop();
postFix.Push(currOperator);
}
// Build the post fix string.
string psString = string.Empty;
foreach (string item in postFix)
{
psString = item + " " + psString;
}
psString = psString.Trim();
return(psString);
}
/// <summary>
/// Convecs an infix string to a post fix string.
/// </summary>
/// <remarks><pre>
/// 2004-07-19 - Jeremy Roberts
/// </pre></remarks>
/// <param name="func">The function to convert</param>
/// <returns>A post fix string.</returns>
protected string Infix2Postfix(string func)
{
func = new InfixExpression(func).Expression;
string[] inFix = func.Split(new[] { ' ' });
var postFix = new Stack <string>();
var operators = new Stack <string>();
string currOperator;
foreach (string token in inFix)
{
if (ExpressionKeywords.IsOperand(token))
{
postFix.Push(token);
}
else if (ExpressionKeywords.OpenGroupOperators.Contains(token))
{
if (operators.Count > 0)
{
var kw = ExpressionKeywords.Keywords.OfType <Procedure>()
.Where(x => x.Name == operators.Peek())
.Select(x => x)
.SingleOrDefault();
if (kw != null &&
kw.VariableOperandsCount)
{
postFix.Push("param_terminator");
}
}
operators.Push(token);
}
else if (ExpressionKeywords.ClosingGroupOperators.Contains(token))
{
Grouping g = ExpressionKeywords.GetGroupingFromClose(token);
currOperator = operators.Pop();
while (currOperator != g.Open)
{
postFix.Push(currOperator);
currOperator = operators.Pop();
}
if (operators.Count > 0 &&
ExpressionKeywords.Functions.Contains(operators.Peek()))
{
postFix.Push(operators.Pop());
}
}
else if (ExpressionKeywords.IsOperator(token))
{
// while precedence of the operator is <= precedence of the token
while (operators.Count > 0)
{
if (ExpressionKeywords.GetPrecedence(token)
<= ExpressionKeywords.GetPrecedence(operators.Peek()))
{
currOperator = operators.Pop();
postFix.Push(currOperator);
}
else
{
break;
}
}
operators.Push(token);
}
else if (ExpressionKeywords.IsVariableDelilimter(token))
{
if (!ExpressionKeywords.OpenGroupOperators.Contains(operators.Peek()))
{
currOperator = operators.Pop();
postFix.Push(currOperator);
}
}
}
while (operators.Count > 0)
{
currOperator = operators.Pop();
postFix.Push(currOperator);
}
// Build the post fix string.
string psString = string.Empty;
foreach (string item in postFix)
{
psString = item + " " + psString;
}
psString = psString.Trim();
return(psString);
}
