How can I do this L1 integral minimization?

1 次查看(过去 30 天)
Greetings,
I have the following integral
where kdx = [pi/16, pi/2], and
I want to minimize the integral above and solving corresponding a_j. But I have no clue how do to it. Can anyone give me some hint?
Thanks.

回答(2 个)

Bruno Luong
Bruno Luong 2018-10-29
编辑:Bruno Luong 2018-10-29
The problem of linear L1 fit (your case); meaning
argmin_x | M*x - y |_l1
argmin sum abs(M*x - y)
can be reformulated and solved by linear programming (opt toolbox required) using slack variables trick as following
n = length(y);
Aeq = [M speye(n) -speye(n)];
Aeqpr=nonzeros(Aeq);
beq = y(:);
c = [zeros(1,size(M,2)) ones(1,2*n)];
LB = [-inf(1,size(M,2)) zeros(1,2*n)];
UB = [];
c = c(:);
LB = LB(:);
UB = UB(:);
x0 = zeros(size(c)); % guess vector
[sol, f, exitflag] = linprog(c,[],[], Aeq, beq, LB, UB, x0);
x = sol(1:size(M,2));
You just need to build M with sin(k*j*dx) and log(dx).
  8 个评论
Sijie Huang
Sijie Huang 2018-10-30
Oh, I see. Sorry I didn't understand your subscript _l1.
Bruno Luong
Bruno Luong 2018-10-30
编辑:Bruno Luong 2018-10-30
I don't know how to type a curly "l" (lowercase L), which is the right notation.

请先登录,再进行评论。


Matt J
Matt J 2018-10-30

类别

Help CenterFile Exchange 中查找有关 Solver Outputs and Iterative Display 的更多信息

Community Treasure Hunt

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

Start Hunting!

Translated by