# polyFilter(a,num,den)

Implements an analog filter with transfer response specified by numerator and denominator polynomials.

### Syntax

o_polyFilter(a,num,den)
  a: Waveform or Spectrum - inputSignal
  num: array 1D numeric - coefficients of numerator polynomial (0 thru n)
  den: array 1D numeric - coefficients of denominator polynomial (0 thru n)
  return: Waveform or Spectrum - output signal formed by passing through defined filter

### Usage

Analog filters are generally specified by a rational polynomial. Use this filter when you know the coefficients of the defining polynomial.

### Location

menu: veeos ==> Signal Processing ==> Modules ==> polyFilter

library: sigLib

### Example

see example in veeos menu

### Notes

In general a linear (analog) filter may be defined by the rational polynomial H(S) where Output(S)=Input(S)*H(S). A typical H(S) rational polynomial may be expressed as:
( n[0]*S^0 + n[1]*S^1 +...n[i]*S^i ) / ( p[0]*S^0 + p[1]*S^1 +...p[i]*S^i )

where n and p are the coefficient vectors that define these polynomials. This function inputs those two vectors, determines H(jF), and filters the input signal appropriately.

### Reference

### Dependencies

### Supported On

VEE 7.0+, all platforms

### See Also

aFilter, AnalogFilter, funcFilter, rootFilter

© 2015-2021. All Rights Reserved. Stan Bischof (stan@worldbadminton.com). Last updated 09 August 2021 18:24.