public Expression CreateExpression(FunctionType typeToCreate, PropertyFunction func, Variable T, Variable TC, Variable PC)
{
Expression expr = null;
switch (typeToCreate)
{
case FunctionType.Polynomial:
//if (func.NumberOfCoefficients < 1)
// throw new InvalidOperationException("Not enough coefficients to create an expression");
EnsureCoefficients(func.Coefficients, 1);
expr = func.Coefficients[0];
for (int i = 1; i < func.NumberOfCoefficients; i++)
{
expr += func.Coefficients[i] * Sym.Pow(T, i);
}
break;
case FunctionType.PolynomialIntegrated:
EnsureCoefficients(func.Coefficients, 1);
expr = func.Coefficients[0] * T;
for (int i = 1; i < func.NumberOfCoefficients; i++)
{
expr += 1.0 / (double)(i + 1) * func.Coefficients[i] * Sym.Pow(T, i + 1);
}
break;
case FunctionType.Dippr106:
if (System.Math.Abs(TC.ValueInSI - func.Coefficients[0].ValueInSI) < 1e-6)
{
EnsureCoefficients(func.Coefficients, 6);
var TR = Sym.Par(T / func.Coefficients[0]);
var h = func.Coefficients[2] + func.Coefficients[3] * TR + func.Coefficients[4] * Sym.Pow(TR, 2) + func.Coefficients[5] * Sym.Pow(TR, 3);
expr = func.Coefficients[1] * Sym.Pow(Sym.Par(1 - TR), h);
}
else
{
EnsureCoefficients(func.Coefficients, 6);
var TR = Sym.Par(T / TC);
var h = func.Coefficients[2] + func.Coefficients[3] * TR + func.Coefficients[4] * Sym.Pow(TR, 2) + func.Coefficients[5] * Sym.Pow(TR, 3);
expr = func.Coefficients[1] * Sym.Pow(Sym.Par(1 - TR), h);
}
break;
case FunctionType.Dippr117:
{
EnsureCoefficients(func.Coefficients, 5);
var Tcon = Sym.Convert(T, func.XUnit);
expr = func.Coefficients[0] * Tcon + func.Coefficients[1] * func.Coefficients[2] * Sym.Coth(func.Coefficients[2] / Tcon) - func.Coefficients[3] * func.Coefficients[4] * Sym.Tanh(func.Coefficients[4] / Tcon);
break;
}
case FunctionType.AlyLee:
{
EnsureCoefficients(func.Coefficients, 5);
Expression Tcon = T;
if (!Unit.AreEquivalent(SI.K, func.XUnit))
{
Tcon = Sym.Convert(T, func.XUnit);
}
expr = func.Coefficients[0] + func.Coefficients[1] * Sym.Pow(Sym.Par((func.Coefficients[2] / Tcon) / Sym.Sinh(func.Coefficients[2] / Tcon)), 2) + func.Coefficients[3] * Sym.Pow(Sym.Par((func.Coefficients[4] / Tcon) / Sym.Cosh(func.Coefficients[4] / Tcon)), 2);
break;
}
case FunctionType.Antoine:
{
EnsureCoefficients(func.Coefficients, 3);
Expression CT = T;
if (!Unit.AreEquivalent(SI.K, func.XUnit))
{
CT = Sym.Convert(T, func.XUnit);
}
expr = Sym.Exp(func.Coefficients[0] - func.Coefficients[1] / Sym.Par(func.Coefficients[2] + CT));
break;
}
case FunctionType.ExtendedAntoine:
{
EnsureCoefficients(func.Coefficients, 7);
Expression CT = T;
if (!Unit.AreEquivalent(SI.K, func.XUnit))
{
CT = Sym.Convert(T, func.XUnit);
}
expr = (Sym.Exp(func.Coefficients[0] + func.Coefficients[1] / Sym.Par(func.Coefficients[2] + CT) + func.Coefficients[3] * CT + func.Coefficients[4] * Sym.Ln(CT) + func.Coefficients[5] * Sym.Pow(CT, func.Coefficients[6])));
break;
}
case FunctionType.Rackett:
{
EnsureCoefficients(func.Coefficients, 4);
var TR = Sym.Convert(T, func.XUnit) / func.Coefficients[2];
expr = func.Coefficients[0] / (Sym.Pow(func.Coefficients[1], 1 + Sym.Pow(Sym.Par(1 - TR), func.Coefficients[3])));
break;
}
case FunctionType.Wagner:
{
EnsureCoefficients(func.Coefficients, 6);
if (TC == null || PC == null)
{
throw new InvalidOperationException("Not enough coefficients to create an expression");
}
var TR = Sym.Convert(T, func.XUnit) / TC;
var tau = Sym.Par(1 - TR);
expr = Sym.Exp(Sym.Ln(PC) + 1 / TR * Sym.Par(func.Coefficients[2] * tau + func.Coefficients[3] * Sym.Pow(tau, 1.5) + func.Coefficients[4] * Sym.Pow(tau, 3) + func.Coefficients[5] * Sym.Pow(tau, 6)));
break;
}
case FunctionType.Watson:
{
EnsureCoefficients(func.Coefficients, 4);
expr = func.Coefficients[0] * Sym.Pow(func.Coefficients[2] - T, func.Coefficients[1]) + func.Coefficients[3];
break;
}
case FunctionType.Dippr102:
{
EnsureCoefficients(func.Coefficients, 4);
expr = func.Coefficients[0] * Sym.Pow(T, func.Coefficients[1]) / (1 + func.Coefficients[2] / T + func.Coefficients[3] / T);
break;
}
case FunctionType.Kirchhoff:
{
EnsureCoefficients(func.Coefficients, 3);
expr = (Sym.Exp(func.Coefficients[0] - func.Coefficients[1] / T + func.Coefficients[2] * Sym.Ln(T)));
break;
}
case FunctionType.Sutherland:
{
EnsureCoefficients(func.Coefficients, 2);
expr = (func.Coefficients[0] * Sym.Sqrt(T)) / (1 + func.Coefficients[1] / T);
break;
}
case FunctionType.Chemsep16:
{
EnsureCoefficients(func.Coefficients, 5);
var a = func.Coefficients[0];
var b = func.Coefficients[1];
var c = func.Coefficients[2];
var d = func.Coefficients[3];
var e = func.Coefficients[4];
expr = a + Sym.Exp(b / T + c + d * T + e * Sym.Pow(T, 2));
break;
}
case FunctionType.Chemsep101:
{
EnsureCoefficients(func.Coefficients, 5);
var a = func.Coefficients[0];
var b = func.Coefficients[1];
var c = func.Coefficients[2];
var d = func.Coefficients[3];
var e = func.Coefficients[4];
expr = (Sym.Exp(a + b / T + c * Sym.Ln(T) + d * Sym.Pow(T, 2.0)));
break;
}
case FunctionType.Chemsep102:
{
EnsureCoefficients(func.Coefficients, 5);
var a = func.Coefficients[0];
var b = func.Coefficients[1];
var c = func.Coefficients[2];
var d = func.Coefficients[3];
var e = func.Coefficients[4];
expr = a * Sym.Pow(T, b) / (1 + c / T + d / Sym.Pow(T, 2));
break;
}
case FunctionType.Chemsep106:
{
EnsureCoefficients(func.Coefficients, 6);
var TR = Sym.Par(T / TC);
var h = func.Coefficients[1] + func.Coefficients[2] * TR + func.Coefficients[3] * Sym.Pow(TR, 2) + func.Coefficients[4] * Sym.Pow(TR, 3);
expr = func.Coefficients[0] * Sym.Pow(Sym.Par(1 - TR), h);
}
break;
default:
throw new InvalidOperationException("Unknown function type" + typeToCreate);
}
return(expr);
}