private Expression ParseID(CharIterator it)
{
char ch = it.Value();
if (IsAlpha(ch) || ch == '@')
{
String varname = ReadString(it);
Variable variable;
if (!fVarsDir.TryGetValue(varname, out variable))
{
variable = new Variable(varname);
variable.fIndex = fVars.Count;
variable.fName = varname;
if (fValues.ContainsKey(varname))
{
variable.fVal = fValues[varname];
}
else
{
variable.fVal = gRnd.Next() % 1000 / 1000.0;
}
fVars.Add(variable);
fVarsDir.Add(varname, variable);
}
var id = new IDExpression(variable);
return(id);
}
else if (ch == '-' || ch == '+' || IsNum(ch))
{
double v = ReadNum(it);
var num = new NumberExpression(v);
return(num);
}
else if (ch == '(')
{
it.MoveNext();
var expr = ParseAdd(it);
if (it.Valid() && it.Value() == ')')
{
it.MoveNext();
return(expr);
}
else
{
throw new Exception("Expect ')'");
}
}
throw new Exception("Need a id or number!");
}
override public String Evaluate()
{
fCalibrationValid = false;
String err = "Done";
var Beta1 = new double[3];
var Beta2 = new double[3];
int N = fCal.Count;
double[,] X = new double[N, 3];
bool linear = true;
try
{
int i = 0;
foreach (var c in fCal)
{
X[i, 1] = Convert.ToDouble(c.fX);
X[i, 2] = Convert.ToDouble(c.fY);
++i;
}
}
catch (Exception)
{
linear = false;
}
if (linear && false)
{
if (N < 3)
{
err = "Too less calibration points!";
return(err);
}
double[] y1 = new double[N];
double[] y2 = new double[N];
for (int i = 0; i < N; ++i)
{
X[i, 0] = 1;
if (fLogX)
{
X[i, 1] = Math.Log(X[i, 1]);
}
if (fLogX)
{
X[i, 2] = Math.Log(X[i, 2]);
}
y1[i] = fCal.ElementAt(i).Ps.X;
y2[i] = fCal.ElementAt(i).Ps.Y;
}
LinearRegression(X, y1, Beta1);
LinearRegression(X, y2, Beta2);
fCalibrationValid = true;
}
else
{
try
{
Calculator cal = new Calculator(fInitialValues);
var pxx = cal.ParseExpression("@pxx");
var pxy = cal.ParseExpression("@pxy");
var pyx = cal.ParseExpression("@pyx");
var pyy = cal.ParseExpression("@pyy");
var px0 = cal.ParseExpression("@px0");
var py0 = cal.ParseExpression("@py0");
Expression chi2 = null;
foreach (var c in fCal)
{
var px = new NumberExpression(c.Ps.X);
var py = new NumberExpression(c.Ps.Y);
var x = cal.ParseExpression(c.fX);
var y = cal.ParseExpression(c.fY);
var c2 = ((pxx * x + pxy * y + px0 - px) ^ 2) + ((pyx * x + pyy * y + py0 - py) ^ 2);
if (chi2 == null)
{
chi2 = c2;
}
else
{
chi2 = chi2 + c2;
}
}
cal.SetRootExpression(chi2);
Minimizer minzer = new Minimizer(cal);
double mn;
var result = minzer.Minimize(out mn);
Beta1[0] = result["@px0"];
Beta1[1] = result["@pxx"];
Beta1[2] = result["@pxy"];
Beta2[0] = result["@py0"];
Beta2[1] = result["@pyx"];
Beta2[2] = result["@pyy"];
fCalibrationValid = true;
err = "chi2 = " + mn.ToString();
}
catch (Exception e)
{
System.Console.WriteLine(e.StackTrace);
err = "Minization error";
}
}
if (fCalibrationValid)
{
// xp = b10 + b1x*x + b1y*y
// yp = b20 + b2x*x + b2y*y
// (xp,yp)^T = (b10,b20)^T + (b1x, b1y // b2x b2y)(x,y)^T
var m = new Matrix(2, 2);
m[0, 0] = Beta1[1];
m[0, 1] = Beta1[2];
m[1, 0] = Beta2[1];
m[1, 1] = Beta2[2];
var d = new Matrix(2, 1);
d[0, 0] = Beta1[0];
d[1, 0] = Beta2[0];
try
{
fQ = m.Invert();
} catch (Exception) {
err = "invert wrong";
return(err);
}
fd = fQ * (-d);
double xvx = Beta1[1];
double xvy = Beta2[1];
double xr = 1 / Math.Sqrt(xvx * xvx + xvy * xvy);
double yvx = Beta1[2];
double yvy = Beta2[2];
double yr = 1 / Math.Sqrt(yvx * yvx + yvy * yvy);
double cc = xvx * yvy - xvy * yvx;
cc = cc * xr * yr;
fXYAngle = 0;
if (cc >= 1)
{
cc = 1;
}
else if (cc <= -1)
{
cc = -1;
}
fXYAngle = Math.Asin(cc) / Math.PI * 180;
// Note the defintion of Y axias in pixels coordinates
fXYAngle = -fXYAngle;
foreach (var r in fResults)
{
OnCompute(r);
}
}
return(err);
}