Dictionary:Quadratic spline

{{#category_index:Q|quadratic spline}} An interpolating operator whose slope $\phi$ at $(x_{1}+\Delta {x})$ is a linear combination of the slope at nearby points $x_{1}$ and $x_{2}$: $\phi ={\phi }_{1}+({\phi }_{2}-{\phi }_{1})\Delta {x}/(x_{2}-x_{1})$.