gr_remez.cc File Reference

#include <gr_remez.h>
#include <cmath>
#include <assert.h>
#include <iostream>
#include <vector>

Include dependency graph for gr_remez.cc:

Defines
#define	LOCAL_BUFFER(T, buf, size)
#define	CONST   const
#define	BANDPASS   1
#define	DIFFERENTIATOR   2
#define	HILBERT   3
#define	NEGATIVE   0
#define	POSITIVE   1
#define	Pi   3.14159265358979323846
#define	Pi2   (2*Pi)
#define	GRIDDENSITY   16
#define	MAXITERATIONS   40
Functions
std::vector< double >	gr_remez (int order, const std::vector< double > &arg_bands, const std::vector< double > &arg_response, const std::vector< double > &arg_weight, const std::string filter_type, int grid_density) throw (std::runtime_error)
	Parks-McClellan FIR filter design.

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Define Documentation

#define BANDPASS   1

Referenced by gr_remez().

#define CONST   const

#define DIFFERENTIATOR   2

Referenced by gr_remez().

#define GRIDDENSITY   16

#define HILBERT   3

Referenced by gr_remez().

#define LOCAL_BUFFER	(	T,
		buf,
		size		)

Value:

std::vector<T> buf ## _vector (size); \
  T *buf = &(buf ## _vector[0])

Referenced by gr_remez().

#define MAXITERATIONS   40

#define NEGATIVE   0

#define Pi   3.14159265358979323846

#define Pi2   (2*Pi)

#define POSITIVE   1

---

Function Documentation

std::vector<double> gr_remez	(	int	order,
		const std::vector< double > &	bands,
		const std::vector< double > &	ampl,
		const std::vector< double > &	error_weight,
		const std::string	filter_type = "bandpass",
		int	grid_density = 16
	)			throw (std::runtime_error)

Parks-McClellan FIR filter design.

Calculates the optimal (in the Chebyshev/minimax sense) FIR filter inpulse reponse given a set of band edges, the desired reponse on those bands, and the weight given to the error in those bands.

Parameters:

	order	filter order (number of taps in the returned filter - 1)
	bands	frequency at the band edges [ b1 e1 b2 e2 b3 e3 ...]
	ampl	desired amplitude at the band edges [ a(b1) a(e1) a(b2) a(e2) ...]
	error_weight	weighting applied to each band (usually 1)
	filter_type	one of "bandpass", "hilbert" or "differentiator"
	grid_density	determines how accurately the filter will be constructed. \ The minimum value is 16; higher values are slower to compute.

Frequency is in the range [0, 1], with 1 being the Nyquist frequency (Fs/2)

Returns:

vector of computed taps

Exceptions:

std::runtime_error

if args are invalid or calculation fails to converge.

References BANDPASS, DIFFERENTIATOR, HILBERT, and LOCAL_BUFFER.