Applied Numerical Mathematics ( IF 2.8 ) Pub Date : 2021-03-18 , DOI: 10.1016/j.apnum.2021.03.009 Rachid Ait-Haddou , Ron Goldman , Marie-Laurence Mazure
We establish the uniform convergence of the control polygons generated by repeated degree elevation of q-Bézier curves (i.e., polynomial curves represented in the q-Bernstein bases of increasing degrees) on , , to a piecewise linear curve with vertices on the original curve. A similar result is proved for , but surprisingly the limit vertices are not on the original curve, but on the -Bézier curve with control polygon taken in the reverse order. We introduce a q-deformation (quantum Lorentz degree) of the classical notion of Lorentz degree for polynomials and we study its properties. As an application of our convergence results, we introduce a notion of q-positivity which guarantees that the q-Lorentz degree is finite. We also obtain upper bounds for the quantum Lorentz degrees. Finally, as a by-product we provide a generalization to polynomials positive on q-lattices of the univariate Pólya theorem concerning polynomials positive on the non-negative axis.
中文翻译:
多项式的量子洛伦兹级数和对q格为正的多项式的Pólya定理
我们建立由q- Bézier曲线(即,以递增的q -Bernstein基数表示的多项式曲线)的重复次数升高生成的控制多边形的一致收敛。, ,到在原始曲线上具有顶点的分段线性曲线。证明了类似的结果,但令人惊讶的是,极限顶点不在原始曲线上,而是在 -Bézier曲线,控制多边形的取反顺序。我们介绍了多项式的Lorentz度经典概念的q形变(量子Lorentz度),并研究了其性质。作为我们收敛结果的一种应用,我们引入了q-正性的概念,该概念保证q -Lorentz度是有限的。我们还获得了量子洛伦兹度的上限。最后,作为副产品,我们对单变量Pólya定理的q格上的正多项式与在非负轴上的正多项式进行了推广。