Error |
This function produces a continuous transition from a left to a right polynomial,
centered at xc, with the width of the transition determined by σ. It is commonly used for
modeling gradual transitions or soft thresholds.
Inheritance HierarchyNamespace: Altaxo.Calc.FitFunctions.Transitions
Assembly: AltaxoCore (in AltaxoCore.dll) Version: 4.8.3448.0 (4.8.3448.0)
SyntaxC#
public class ErrorFunctionFromTo : IFitFunctionWithDerivative, IFitFunction, IImmutable, IEquatable<ErrorFunctionFromTo>
The ErrorFunctionFromTo type exposes the following members.
Constructors| Name | Description | |
|---|---|---|
 | ErrorFunctionFromTo | Initializes a new instance of the ErrorFunctionFromTo class, with both polynomial orders set to zero. |
| ErrorFunctionFromTo(Int32, Int32) | Initializes a new instance of the ErrorFunctionFromTo class. |
Properties| Name | Description | |
|---|---|---|
 | NumberOfDependentVariables | Number of dependent variables (i.e. y, in Altaxo this is commonly called v (like value)). |
| NumberOfIndependentVariables | Number of independent variables (i.e. x). |
| NumberOfParameters | Number of parameters of this fit function. |
| PolynomialOrderLeft | Gets the order of the left polynomial segment. |
| PolynomialOrderRight | Gets the polynomial order of the right segment. |
Methods| Name | Description | |
|---|---|---|
 | Create | Factory used by the fit function registry. |
| DefaultParameterValue | Returns a default parameter value. You must ensure that the fit function would generate values with those default parameters. |
| DefaultVarianceScaling | Returns the default variance scaling for the dependent variable i. |
| DependentVariableName | Returns the ith dependent variable name. |
| Evaluate(Double, Double, Double) | This evaluates a function value. |
| Evaluate(IROMatrixDouble, IReadOnlyListDouble, IVectorDouble, IReadOnlyListBoolean) | Evaluates the function values at multiple x-points. |
| Evaluate(Double, Double, Double, ReadOnlySpanDouble, ReadOnlySpanDouble) | Evaluates a smoothed step function that transitions from a left polynomial to a right polynomial value using an error function profile. |
| EvaluateDerivative | Evaluates the gradient of the function with respect to the parameters. |
 | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object) |
| GetParameterBoundariesHardLimit | Gets the parameter boundaries that are really a hard limit, i.e. outside those limits, the function would probably evaluate NaN values, or makes no sense. |
| GetParameterBoundariesSoftLimit | Gets the intended parameter boundaries. This are soft limits, boundaries so that the intended purpose of the fit function is fullfilled. Example: in the exponential decay Exp(-a*t) a is intended to be positive. This is a soft limit, and not a hard limit, because a could be also negative, and the fit nevertheless would succeed. |
| GetType | Gets the Type of the current instance. (Inherited from Object) |
| IndependentVariableName | Returns the ith independent variable name. |
| MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object) |
| ParameterName | Returns the ith parameter name. |
| WithPolynomialOrderLeft | Creates a new instance with the provided order for the left polynomial segment. |
| WithPolynomialOrderRight | Creates a new instance with the provided order for the right polynomial segment. |
Events| Name | Description | |
|---|---|---|
 | Changed | Occurs when the fit function changed, including number or name of parameters, independent variables, dependent variables, or the scaling. |
RemarksThis function is defined by at least four parameters: 'xc', 'σ', which determine position and width of the transition, and a0 and b0, which are the polynomial coefficients of zero order
of the left and the right polynomial, respectively. It produces a
sigmoidal transition from the 'a0' value to the 'b0' value, centered at 'xc' with the width determined by 'σ'.
See Also