horner - polynomial/rational evaluation

Calling Sequence

horner(P,x)

Parameters

• P : polynomial or rational matrix
• x : real number or polynomial or rational

Description

evaluates the polynomial or rational matrix P = P(s) when the variable s of the polynomial is replaced by x:

horner(P,x)=P(x)

Example (Bilinear transform): Assume P = P(s) is a rational matrix then the rational matrix P((1+s)/(1-s)) is obtained by horner(P,(1+s)/(1-s)).

To evaluate a rational matrix at given frequencies use preferably the freq primitive.

Examples

s=poly(0,'s');M=[s,1/s];
horner(M,1)
horner(M,%i)
horner(M,1/s)
 

See Also

freq  repfreq  evstr