help me in understanding the code
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clear,
clc;
pdf='exp(-(x-m).^2/2/sigma^2)/sqrt(2*pi)/sigma'; %Gaussian pdf of x
xf=inline(['x.*' pdf],'x','m','sigma');
f=inline(pdf,'x','m','sigma');
m=0; sigma=1; % Mean and variance of the random variable x
b0=-3; bN=3; % Given least/greatest value of the random variable x
for N=5:6 % Number of quantization intervals
delta=(bN-b0)/N;
b=b0+[0:N]*delta;
msqe=0; % Mean-Square Quantization Error
for i=1:N % Centroid of each interval
tmp1=quad(xf,b(i),b(i+1),0.01,[],m,sigma);
tmp2=quad(f,b(i),b(i+1),0.01,[],m,sigma);
tmp=tmp1/tmp2; c(i)=tmp; % Eq.(4.1.1)
x2f=inline(['(x-tmp).^2.*' pdf],'x','m','sigma','tmp');
msqe=msqe+quad(x2f,b(i),b(i+1),0.01,[],m,sigma,tmp); % Eq.(4.1.2)
end
% Resulting boundary vector and centroid vector
x=b0+(bN-b0)/1000*[0:1000];
y(find(x<b(1)))=c(1); % Left-most interval
for i=1:N, y(find(b(i)<=x&x<b(i+1)))=c(i); end
y(find(x>=b(N+1)))=c(N); % Right-most interval
subplot(2,2,N-4),
plot(x,y),
hold on,
grid on % Quantization graph
m=0; sigma=1; fx=feval(f,x,m,sigma);
plot(x,fx,'r:') ;
% Resulting MSQE
end
2 Comments
Walter Roberson
on 15 Apr 2012
Please be more specific in your question. For example are you stuck at the "clc" call, or are you stuck on logical indexing, or are you stuck in understanding what the [] argument to quad() means?
Rick Rosson
on 15 Apr 2012
Help us by asking a specific question.
Answers (0)
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