/// <summary>
/// Determines whether the specified <see cref="ParametricExpression"/> is equal to the
/// current <see cref="ParametricExpression"/>.
/// </summary>
/// <param name="other">The <see cref="ParametricExpression"/> to compare with the current
/// <see cref="ParametricExpression"/>.</param>
/// <returns>
/// true if the specified <see cref="ParametricExpression"/> is equal to the current
/// <see cref="ParametricExpression"/>; otherwise, false.
/// </returns>
public bool Equals(ParametricExpression other)
{
if (ReferenceEquals(null, other)) return false;
if (ReferenceEquals(this, other)) return true;
return Equals(other.XExpression.OriginalExpression, XExpression.OriginalExpression) &&
Equals(other.YExpression.OriginalExpression, YExpression.OriginalExpression);
}
public static double CalculateDerivative(Calculator calc, ParametricExpression expr, double t, out PointD result)
{
calc.GraphingArgumentValue = t;
double x1 = calc.Evaluate(expr.XExpression);
double y1 = calc.Evaluate(expr.YExpression);
calc.GraphingArgumentValue = t + DeltaX;
double x2 = calc.Evaluate(expr.XExpression);
double y2 = calc.Evaluate(expr.YExpression);
double fPrime1 = (x2 - x1) / DeltaX;
double fPrime2 = (y2 - y1) / DeltaX;
result = new PointD(x1, y1);
return fPrime2 / fPrime1;
}
public ExpressionInfo(UncompiledExpression expr, CompiledDomain domain = null)
{
if (expr is UncompiledStandardExpression)
{
var stdExpr = expr as UncompiledStandardExpression;
Expression = new StandardExpression(expr.Slot, expr.Type, stdExpr.Expression, domain);
}
else if (expr is UncompiledParametricExpression)
{
var paraExpr = expr as UncompiledParametricExpression;
Expression = new ParametricExpression(expr.Slot, paraExpr.XExpression, paraExpr.YExpression, domain);
}
else
{
throw new ArgumentException("expr");
}
OriginalUncompiled = expr;
Enabled = true;
}
