57 lines
1.5 KiB
Matlab
57 lines
1.5 KiB
Matlab
function [ SigmaInv] = CalcSigmaCCNFflat(alphas, betas, n, precalcQ2withoutBeta, precalc_eye, precalc_zeros)
|
|
%CALCSIGMAPRF Summary of this function goes here
|
|
% Detailed explanation goes here
|
|
% constructing the sigma
|
|
|
|
% A = zeros(n);
|
|
%
|
|
% for i=1:n
|
|
%
|
|
% A(i,i) = alphas' * mask(i,:)';
|
|
%
|
|
% end
|
|
|
|
% this is simplification of above code
|
|
% if(useIndicators)
|
|
% A = diag(mask * alphas);
|
|
% else
|
|
|
|
% A = sum(alphas) .* eye(n);
|
|
A = sum(alphas) .* precalc_eye;
|
|
% A = sum(alphas) * eye(n);
|
|
% not faster
|
|
% a = mtimesx(sum(alphas), eye(n), 'SPEED');
|
|
% a2 = mtimesx(sum(alphas), eye(n), 'SPEEDOMP');
|
|
% end
|
|
|
|
% calculating the B from the paper
|
|
|
|
% for i=1:n
|
|
% for j=1:n
|
|
%
|
|
% if(i == j)
|
|
% q2(i,j) = beta * (sum(S(i,:)) - S(i,i));
|
|
% else
|
|
% q2(i,j) = -beta * S(i,j);
|
|
% end
|
|
% end
|
|
% end
|
|
|
|
% the above code can be simplified by the following lines of code
|
|
% using the precalculated lower triangular elements of B without beta
|
|
Btmp = precalcQ2withoutBeta * betas;
|
|
% not faster
|
|
% Btmp = mtimesx(precalcQ2withoutBeta, betas, 'SPEED');
|
|
% Btmp = mtimesx(precalcQ2withoutBeta, betas, 'SPEEDOMP');
|
|
% now make it into a square symmetric matrix
|
|
% B = zeros(n,n);
|
|
B = precalc_zeros;
|
|
on = tril(true(n,n));
|
|
B(on) = Btmp;
|
|
B = B';
|
|
B(on) = Btmp;
|
|
|
|
SigmaInv = 2 * (A + B);
|
|
|
|
end
|
|
|