摘 要:提出了一个基于CODIC的计算Bernstein多项式的移位-加算法。该算法可以在存在于许多领域的基本计算系统中实现。证明了算法的收敛性,给出了误差分析,做了数值实验,验证了算法的有效性和效率。
关键词:Bernstein多项式;CORDIC;移位-加算法;基本计算系统
在高级计算系统中,可以很容易地找到Bernstein多项式的算法[3]。例如,在Mathematica中,可以用BernsteinBasis[n,i,t]计算。用高级语言编程计算Bernstein多项式也非常容易。本文讨论如何在基本计算系统(仅具备移位、加和逻辑运算功能的计算系统)中计算Bernstein多项式。基本计算系统存在于许多系统中,例如工业控制系统、军事应用系统、医疗应用系统等。典型的有单片机系统和FPGA(Field Programmable Gate Arrays)等。
CORDIC算法是可计算多种基本初等函数的移位-加算法[4-6]。参考文献[7-8]扩展了CORDIC算法,其收敛性和误差估计在参考文献[7]中做了分析。随着硬件技术的发展,这些快速统一移位-加算法可以用硬件实现,而且不需使用乘法器[9],成本较低,也可以用汇编语言编程实现。本文提出一个基于CORDIC算法的Bernstein多项式移位-加算法。
参考文献
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