Deconvolution of a polynomial and exponential function

7 次查看(过去 30 天)
I got the same problem with following link:
I got trouble using Bayesian deconvolution
here I already got wt(z) and a'(z) with same one dimension size array
I have no idea how to got iterative.
If need my data, I will give my data. thanks a lot ><
  4 个评论
高飞 支
高飞 支 2023-12-17
移动:John D'Errico 2023-12-17
I have the same trouble have you solved it?can you give me some advices?
Rui
Rui 2024-8-6
hello, larry liu
i am doing the same work as you did, did u use the Bayes iteration that you showed in the picture? cuz i try to deal with time constant in this way. It doesn't work..

请先登录,再进行评论。

回答(1 个)

Yash
Yash 2023-11-24
编辑:Yash 2023-11-24
Hi Larry,
I understand that you are facing issues while using the "deconv" function in MATLAB. "deconv(y,h)" deconvolves a vector "h" out of a vector "y" using polynomial long division, and returns the quotient "x" and remainder "r" such that "y = conv(x,h) + r".
Given that you already have a deconvolution function in your case, you may not need to use the "deconv" function. Instead, you can make an initial guess for "R(z)" and then obtain the approximation iteratively using a loop as follows:
n = length(df2);
w = Wzinstead';
a = df2';
R = randi(1000,n,1)/1000; % Initial guess, random values
nIter = 10;
for i=1:1:nIter
R1=R*(corr(w, a./(conv(w,R,'same'))));
R=R1;
end
Hope this helps you address the issue.
  1 个评论
yicong
yicong 2024-9-6
% Define initial parameters
R1 = 6.3;
R2 = 6.3;
R3 = 6.3;
tau1 = 1e-5;
tau2 = 1e-2;
tau3 = 1e1;
% Define the time range
t_min = 1e-6;
t_max = 1e2;
% Calculate the number of interpolation points
num_points_per_decade = 20;
num_decades = log10(t_max) - log10(t_min);
num_points = round(num_points_per_decade * num_decades);
% Generate logarithmically spaced time points
t_interp = logspace(log10(t_min), log10(t_max), num_points);
z_interp = log(t_interp);
% Calculate the analytical model a(t)
a_t = R1 * (1 - exp(-exp(log(t_interp))/tau1)) + ...
R2 * (1 - exp(-exp(log(t_interp))/tau2)) + ...
R3 * (1 - exp(-exp(log(t_interp))/tau3));
% Use gradient to compute da/dz
da_dz = gradient(a_t, z_interp);
% Define W(z) = exp(z - exp(z))
W_z = exp(z_interp - exp(z_interp));
% Uncomment to normalize each column of W_z
% for l = 1:num_points
% W_z(:, l) = W_z(:, l) / sum(W_z(:, l)); % Normalize each column
% end
max_iterations = 100; % Maximum number of iterations
tolerance = 1e-6; % Convergence threshold
% Initialize Psi(z) with da/dz
Psi_z = da_dz';
w=W_z';
a=da_dz';
% Iterative correction
for iter = 1:1:max_iterations
R1=Psi_z*(corr(w, a./(conv(w,Psi_z,'same'))));
Psi_z=R1;
end
% Plot the results
figure;
subplot(3,1,1);
plot(z_interp, da_dz);
title('da/dz vs z');
xlabel('z');
ylabel('da/dz');
subplot(3,1,2);
plot(z_interp, W_z);
title('W(z)');
xlabel('z');
ylabel('W(z)');
subplot(3,1,3);
plot(z_interp, Psi_z);
title('\Psi(z) after Van Cittert Deconvolution');
xlabel('z');
ylabel('\Psi(z)');
-----------
I apply your code here while get wrong time constant result.

请先登录,再进行评论。

类别

Help CenterFile Exchange 中查找有关 Polynomials 的更多信息

产品

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by