ISplineKernel1D.EvaluateWithDerivatives Method

(double , double , double ) EvaluateWithDerivatives(
	double t,
	ReadOnlySpan<double> x,
	ReadOnlySpan<double> f
)

Function EvaluateWithDerivatives ( 
	t As Double,
	x As ReadOnlySpan(Of Double),
	f As ReadOnlySpan(Of Double)
) As ( As Double,  As Double,  As Double)

ValueTuple<double, double, double> EvaluateWithDerivatives(
	double t, 
	ReadOnlySpan<double> x, 
	ReadOnlySpan<double> f
)

abstract EvaluateWithDerivatives : 
        t : float * 
        x : ReadOnlySpan<float> * 
        f : ReadOnlySpan<float> -> ValueTuple<float, float, float> 

Parameters

t  Double

The target coordinate in physical units.

x  ReadOnlySpan<Double>

The sample locations (knot positions) used by the kernel. Length must equal Width.

f  ReadOnlySpan<Double>

The function values at the sample locations. Length must equal Width.

Return Value

• Item1: The interpolated value at t
• Item2: The first derivative df/dt at t
• Item3: The second derivative d²f/dt² at t

Both derivatives are computed with respect to the physical coordinate, not a normalized parameter.

This method must not allocate memory.

Reference