computing daubechies wavelet with different scales
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hello please i need to compute and plot the daubechies wavelet, i also may need to change the scale of the wavelet please help me . i found this function but i dont understand where is the scale parameter and how to plot the wavelet
function [h_0,h_1] = daubcqf(N,TYPE)
% [h_0,h_1] = daubcqf(N,TYPE);
%
% Function computes the Daubechies' scaling and wavelet filters
% (normalized to sqrt(2)).
%
% Input:
% N : Length of filter (must be even)
% TYPE : Optional parameter that distinguishes the minimum phase,
% maximum phase and mid-phase solutions ('min', 'max', or
% 'mid'). If no argument is specified, the minimum phase
% solution is used.
%
% Output:
% h_0 : Minimal phase Daubechies' scaling filter
% h_1 : Minimal phase Daubechies' wavelet filter
%
% Example:
% N = 4;
% TYPE = 'min';
% [h_0,h_1] = daubcqf(N,TYPE)
% h_0 = 0.4830 0.8365 0.2241 -0.1294
% h_1 = 0.1294 0.2241 -0.8365 0.4830
%
if(nargin < 2),
TYPE = 'min';
end;
if(rem(N,2) ~= 0),
error('No Daubechies filter exists for ODD length');
end;
K = N/2;
a = 1;
p = 1;
q = 1;
h_0 = [1 1];
for j = 1:K-1,
a = -a * 0.25 * (j + K - 1)/j;
h_0 = [0 h_0] + [h_0 0];
p = [0 -p] + [p 0];
p = [0 -p] + [p 0];
q = [0 q 0] + a*p;
end;
q = sort(roots(q));
qt = q(1:K-1);
if TYPE=='mid',
if rem(K,2)==1,
qt = q([1:4:N-2 2:4:N-2]);
else
qt = q([1 4:4:K-1 5:4:K-1 N-3:-4:K N-4:-4:K]);
end;
end;
h_0 = conv(h_0,real(poly(qt)));
h_0 = sqrt(2)*h_0/sum(h_0); %Normalize to sqrt(2);
if(TYPE=='max'),
h_0 = fliplr(h_0);
end;
if(abs(sum(h_0 .^ 2))-1 > 1e-4)
error('Numerically unstable for this value of "N".');
end;
h_1 = rot90(h_0,2);
h_1(1:2:N)=-h_1(1:2:N);
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