資源簡介
貝葉斯壓縮感知和分布式貝葉斯壓縮感知的算法實現,很好的范例
代碼片段和文件信息
function?[weightsusedsigma2errbarsbasis]?=?BCS_fast_rvm(PHItsigma2etaadaptiveoptimalscale)
%------------------------------------------------------------------
%?The?BCS?algorithm?for?the?following?paper:
%?“Bayesian?Compressive?Sesning“?(Preprint?2007).?The?algorithm?
%?adopts?from?the?fast?RVM?algorithm?[Tipping?&?Faul?2003].
%?Coded?by:?Shihao?Ji?ECE?Duke?University
%?last?change:?Jan.?2?2007
%?You?are?suggested?to?use?mt_CS.m?for?improved?robustness
%------------------------------------------------------------------
%?Input?for?BCS:
%???PHI:?projection?matrix
%???t:???CS?measurements
%???sigma2:?initial?noise?variance
%??????If?measurement?noise?exists?and/or?w?is?not?truely?sparse?
%?????????????then?sigma2?=?std(t)^2/1e2?(suggested)
%??????If?no?measurement?noise?and?w?is?truely?sparse
%?????????????then?sigma2?=?std(t)^2/1e6?(suggested)
%??????This?term?is?in?fact?not?updated?in?the?implementation?to?allow?
%??????the?fast?algorithm.?For?this?reason?you?are?recommended?to?use
%??????mt_CS.m?in?which?the?noise?variance?is?marginalized.
%???eta:?threshold?for?stopping?the?algorithm?(suggested?value:?1e-8)
%?Input?for?Adaptive?CS:
%???adaptive:?generate?basis?for?adpative?CS??(default:?0)
%???optimal:?use?the?rigorous?implementation?of?adaptive?CS??(default:?1)
%???scale:?diagonal?loading?parameter?(default:?0.1)
%?Output:
%???weights:??sparse?weights
%???used:?????the?positions?of?sparse?weights
%???sigma2:???re-estimated?noise?variance
%???errbars:??one?standard?deviation?around?the?sparse?weights
%???basis:????if?adaptive==1?then?basis?=?the?next?projection?vector
%
if?nargin?5
????adaptive?=?0;
end
if?nargin?6
????optimal?=?1;
end
if?nargin?7
????scale?=?0.1;
end
%?find?initial?alpha
[NM]?=?size(PHI);
PHIt?=?PHI‘*t;
PHI2?=?sum(PHI.^2)‘;
ratio?=?(PHIt.^2)./PHI2;
[maxrindex]?=?max(ratio);
alpha?=?PHI2(index)/(maxr-sigma2);
%?compute?initial?mu?Sig?S?Q
phi?=?PHI(:index);
Hessian?=?alpha?+?phi‘*phi/sigma2;
Sig?=?1/Hessian;
mu?=?Sig*PHIt(index)/sigma2;
left?=?PHI‘*phi/sigma2;
S?=?PHI2/sigma2-Sig*left.^2;
Q?=?PHIt/sigma2-Sig*PHIt(index)/sigma2*left;
%
for?count?=?1:10000
????s?=?S;?q?=?Q;
????s(index)?=?alpha.*S(index)./(alpha-S(index));
????q(index)?=?alpha.*Q(index)./(alpha-S(index));
????theta?=?q.^2-s;
????%?choice?the?next?alpha?that?maximizes?marginal?likelihood
????ml?=?-inf*ones(1M);
????ig0?=?find(theta>0);
????%?index?for?re-estimate
????[irefoowhich]?=?intersect(ig0index);
????if?~isempty(ire)
????????Alpha?=?s(ire).^2./theta(ire);
????????delta?=?(alpha(which)-Alpha)./(Alpha.*alpha(which));
????????ml(ire)?=?Q(ire).^2.*delta./(S(ire).*delta+1)-log(1+S(ire).*delta);
????end
????%?index?for?adding
????iad?=?setdiff(ig0ire);
????if?~isempty(iad)
????????ml(iad)?=?(Q(iad).^2-S(iad))./S(iad)+log(S(iad)./(Q(iad).^2));
????end
????is0?=?setdiff([1:M]ig0);
????%?index?for?deleting
????[idefoowhich]?=?intersect(is0inde
?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件????????2664??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\README.txt
?????文件???????60236??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\approx_results.mat
?????文件????????5463??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\BCS_fast_rvm.m
?????文件????????2096??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\Fig2.m
?????文件????????1262??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\Fig4_ab.m
?????文件????????3536??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\l1qc_logbarrier.m
?????文件????????4413??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\l1qc_newton.m
?????文件????????1696??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\multi_approx_measures.m
?????文件????????1763??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\multi_optimized_measures.m
?????文件????????1514??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\multi_random_measures.m
?????文件???????60300??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\optimized_results.mat
?????文件???????60084??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\BCS_demo\random_results.mat
?????文件?????????955??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\l1dantzig_example.m
?????文件?????????644??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\l1decode_example.m
?????文件????????1003??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\l1eq_example.m
?????文件????????1114??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\l1qc_example.m
?????文件????????1448??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\README
?????文件????????1449??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\tvdantzig_example.m
?????文件????????1396??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\tveq_example.m
?????文件?????????867??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\tveq_phantom_example.m
?????文件????????1424??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\tvqc_example.m
?????文件????????1405??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\tvqc_quantization_example.m
?????文件???????65728??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\Data\boats.mat
?????文件???????65728??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\Data\camera.mat
?????文件?????????543??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\Data\RandomStates.mat
?????文件?????????718??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\Measurements\At_f.m
?????文件?????????613??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\Measurements\At_fhp.m
?????文件?????????659??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\Measurements\A_f.m
?????文件?????????576??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\Measurements\A_fhp.m
?????文件?????????832??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\Measurements\LineMask.m
?????文件????????6601??2020-10-21?13:07??BCS_CODE\bcs_ver0.1\l1magic\Notes\l1magic.bib
............此處省略46個文件信息
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