Cubic Hermite spline

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In the mathematical subfield of numerical analysis a cubic Hermite spline, named in honor of Charles Hermite, is a third-degree spline with each polynomial of the spline in Hermite form. The Hermite form consists of two control points and two control tangents for each polynomial.

On each subinterval, given a starting point p0 and an ending point p1 with starting tangent m0 and ending tangent m1, the polynomial can be defined by

\mathbf{p}(t) = (2t^3-3t^2+1)\mathbf{p}_0 + (t^3-2t^2+t)\mathbf{m}_0 + (-2t^3+3t^2)\mathbf{p}_1 +(t^3-t^2)\mathbf{m}_1

where t ∈ [0, 1].

The four Hermite basis functions can be defined as

h_{00}(t) = 2t^3-3t^2+1 \,\!
h_{10}(t) = t^3-2t^2+t \,\!
h_{01}(t) = -2t^3+3t^2 \,\!
h_{11}(t) = t^3-t^2   \,\!

to give the polynomial as

\mathbf{p}(t) = h_{00}(t)\mathbf{p}_0 + h_{10}(t)\mathbf{m}_0 + h_{01}(t)\mathbf{p}_1 + h_{11}(t)\mathbf{m}_1.

Since each subinterval must share tangents with neighboring subintervals, many techniques exist to determine values for shared tangents.

Some of the techniques for creating cubic Hermite splines include:

[edit] See also

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