testchareqn.html

syntfil[TestCharEqn] - verify the transfer and the characteristic function

Calling sequence:

TestCharEqn(pol, chpol, var)

Parameters:

pol - inverse transfer function (output from functions cited in references "See also")

chpol - characteristic function (output from functions cited in references "See also")

var - variable symbol in previous functions

Description:

Verify correctness of the computation.
If the transfer and characteristic functions are correct, then the function returns very small number. Otherwise, the function returns number that is much larger than zero.
The accuracy of the approximation computation can be controlled by changing environment variable Digits .

Example:

> with(syntfil):

Compute Butterworth approximation

> pol,chpol:=Butterworth(3,2,3,s);

> TestCharEqn(pol,chpol,s);