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Member of the filter design class.

Syntax

y = firls(n, f, a)

y = firls(n, f, a, w)

y = firls(n, f, a, option)

y = firls(n, f, a, w, option)

Description

Designs a least-squares linear FIR filter.

Details

Examples

Inputs

Name	Description
n	Specifies the filter order. n is a nonnegative integer.
f	Specifies the normalized frequencies at which you want to take samples. The size of f must be even. f is a vector.
a	Specifies the amplitudes at each of the f frequencies. a is a vector of the same size as f.
w	Specifies the weight. w is a vector that is half the length of f.
option	Specifies the odd-symmetry filter to design. option is a string that accepts the following values. 'differentiator' Designs a differentiator filter. 'Hilbert' Designs a Hilbert filter.

Outputs

Name	Description
y	Returns the filter coefficients of order n. y is a real vector.

Details

If f = [0.1, 0.2, 0.3, 0.4] and a = [1, 1, 0, 0], LabVIEW ignores the interval [0.2, 0.3] and attempts to implement a filter whose amplitude is 1 in [0.1, 0.2] and 0 in [0.3, 0.4].

Examples

N = 11;
F = [0.1, 0.2, 0.3, 0.4];
A = [1, 1, 0, 0];
Y = firls(N, F, A)

Related Topics

fir1
fir2
firgauss