PolynomialFract32

Overview

Sample-by-sample polynomial nonlinearity

Discussion

Polynomial nonlinearity, computed on a sample by sample basis. The module implements the following equation:

\(y[n]=x[n]^{N-1}c[0]+x[n]^{N-2}c[1]+...+x[n]c[N-2] + c[N-1]\)

where y is the output, x is the input, and c is the array of polynomial coefficients.

Module Pack

Standard

ClassID

classID = 168

Type Definition

typedef struct _ModulePolynomialFract32
{
ModuleInstanceDescriptor instance;            // Common Audio Weaver module instance structure
INT32 numCoeffs;                              // Number of coefficients in the polynomial
INT32 postShift;                              // Number of bits to shift
FLOAT32* coeffs;                              // Coefficient array in descending order. X^(N-1)*C[0] + X^(N-2)*C[1]+ ...
fract32* coeffsFract32;                       // Coefficient array in descending order. X^(N-1)*C[0] + X^(N-2)*C[1]+ ...
} ModulePolynomialFract32Class;

Variables

Properties

Name	Type	Usage	isHidden	Default Value	Range
numCoeffs	int	const	0	3	Unrestricted
postShift	int	derived	1	1	Unrestricted
coeffs	float*	parameter	0	[3 x 1]	Unrestricted
coeffsFract32	fract32*	derived	0	[3 x 1]	Unrestricted

Pins

Input Pins


Name	in
Description	audio input
Data type	fract32
Channel range	Unrestricted
Block size range	Unrestricted
Sample rate range	Unrestricted
Complex support	Real

Output Pins


Name	out
Description	audio output
Data Type	fract32

Matlab Usage

File Name: polynomial_fract32_module.m 
 M=polynomial_fract32_module(NAME, NUMCOEFFS) 
 Creates a sample-by-sample polynomial nonlinearity for us in the Audio 
 Weaver environment.  The module has a single multi-channel input pin. 
 Arguments: 
    NAME - name of the module. 
    NUMCOEFFS - number of coefficients in the polynomial. 

 The order of the polynomial (the highest power of x) is NUMCOEFFS-1. 
 The polynomial coefficients use the same ordering as the MATLAB 
 polyval function.