In this section we apply Axioms ,
,
and
to the analysis of the running time of a program
which evaluates the value of a polynomial.
That is, given the n+1 coefficients
,
and a value x, we wish to compute the following summation
The usual way to evaluate such
polynomials is to use Horner's rule ,
which is an algorithm to compute the summation without
requiring the computation of arbitrary powers of x.
The algorithm to compute this summation is given in Program .
Table
gives the running times of each of the
executable statements in Program
.
Program: Program to compute using Horner's rule.
Summing the entries in Table
we get that the running time, T(n),
of Program
is
where
and
.