zeta1.m

来自「一种基于压缩感知技术的图像重建程序」· M 代码 · 共 29 行

function xi = zeta1(s)
%  xi = zeta1(s)
%
%  zeta1(s) is the logarithmic derivative of
%         2 Phi(s)
%  where  Phi(s) denotes normal CDF
%  Eqn (6.9) in HDCSPNP2P
%  zeta1(s) = phi(s)/Phi(s)
%  where phi(s) is the normal density.
%  We use the fact that phi(s)/Phi(s)
%  is related to the so-called Mills'' ratio. 
% Phi =  1/2 - erf(-s./sqrt(2))./2;
% lphi = exp(-s.^2./2)./sqrt(2*pi);
% xi = lphi./Phi;

xi = abs(s)./MillsM(s);

%
% Copyright (c) 2006. David Donoho
%  

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% Part of SparseLab Version:100
% Created Tuesday March 28, 2006
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