internal MathNode AddChild(MathNode n)
{
_child.Add(n);
_childCount++;
return(_child[_child.Count - 1]); // should be the same as n?????
}
private MathNode Parse(string s)
{
if (string.IsNullOrEmpty(s))
{
return(new MathNode(NodeType.Real, "0", _useRadians));
}
if (IsNumeric(s))
{
return(new MathNode(NodeType.Real, s, _useRadians));
}
if (s[0] == '$')
{
if (IsNumeric(s.Substring(1)))
{
return(_tempNode[int.Parse(s.Substring(1))]);
}
}
var sLo = s.ToLower();
if (sLo.Length == 1)
{
if (sLo[0] >= 'a' && sLo[0] <= 'z')
{
return(new MathNode(NodeType.Variable, sLo, _useRadians));
}
}
switch (sLo)
{
case "pi":
return(new MathNode(NodeType.Variable, sLo, _useRadians));
}
var bracStt = s.LastIndexOf('(');
if (bracStt > -1)
{
var bracEnd = s.IndexOf(")", bracStt);
if (bracEnd < 0)
{
_errMsg += "Missing ')'\n";
return(new MathNode(NodeType.Real, "0", _useRadians));
}
bool isParam;
if (bracStt == 0)
{
isParam = false;
}
else
{
var prefix = s.Substring(bracStt - 1, 1);
isParam = _operators.IndexOf(prefix) <= -1;
}
if (!isParam)
{
_tempNode.Add(Parse(s.Substring(bracStt + 1, bracEnd - bracStt - 1)));
return(Parse(
s.Substring(0, bracStt) +
"$" +
(_tempNode.Count - 1).ToString() +
s.Substring(bracEnd + 1, s.Length - bracEnd - 1)
));
}
else
{
var startM = -1;
for (var u = bracStt - 1; u > -1; u--)
{
var found = _operators.IndexOf(s.Substring(u, 1));
if (found > -1)
{
startM = u;
break;
}
}
var nnew = new MathNode(NodeType.Function, s.Substring(startM + 1, bracStt - 1 - startM), _useRadians);
nnew.AddChild(Parse(s.Substring(bracStt + 1, bracEnd - bracStt - 1)));
_tempNode.Add(nnew);
return(Parse(
s.Substring(0, startM + 1) +
"$" +
(_tempNode.Count - 1).ToString() +
s.Substring(bracEnd + 1, s.Length - bracEnd - 1)
));
}
}
int k;
var k1 = s.LastIndexOf('+');
var k2 = s.LastIndexOf('-');
if (k1 > -1 || k2 > -1)
{
if (k1 > k2)
{
k = k1;
var nnew = new MathNode(NodeType.Operation, "add", _useRadians);
nnew.AddChild(Parse(s.Substring(0, k)));
nnew.AddChild(Parse(s.Substring(k + 1, s.Length - k - 1)));
return(nnew);
}
else
{
k = k2;
var nnew = new MathNode(NodeType.Operation, "sub", _useRadians);
nnew.AddChild(Parse(s.Substring(0, k)));
nnew.AddChild(Parse(s.Substring(k + 1, s.Length - k - 1)));
return(nnew);
}
}
k1 = s.LastIndexOf('*');
k2 = s.LastIndexOf('/');
if (k1 > -1 || k2 > -1)
{
if (k1 > k2)
{
k = k1;
var nnew = new MathNode(NodeType.Operation, "mult", _useRadians);
nnew.AddChild(Parse(s.Substring(0, k)));
nnew.AddChild(Parse(s.Substring(k + 1, s.Length - k - 1)));
return(nnew);
}
else
{
k = k2;
var nnew = new MathNode(NodeType.Operation, "div", _useRadians);
nnew.AddChild(Parse(s.Substring(0, k)));
nnew.AddChild(Parse(s.Substring(k + 1, s.Length - k - 1)));
return(nnew);
}
}
k = s.IndexOf('^');
if (k > -1)
{
var nnew = new MathNode(NodeType.Operation, "pow", _useRadians);
nnew.AddChild(Parse(s.Substring(0, k)));
nnew.AddChild(Parse(s.Substring(k + 1, s.Length - k - 1)));
return(nnew);
}
if (IsNumeric(s))
{
return(new MathNode(NodeType.Real, s, _useRadians));
}
else
{
if (s.Length == 0)
{
return(new MathNode(NodeType.Real, "0", _useRadians));
}
else
{
_errMsg += "'" + s + "' is not a number.\n";
return(new MathNode(NodeType.Real, "0", _useRadians));
}
}
}
