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Deleted trailing white spaces.

time-shift
Stéphane Adjemian (Charybdis) 2012-03-03 18:28:15 +01:00
parent 978f29f59d
commit bbf63f0da9
1 changed files with 11 additions and 11 deletions
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22
matlab/simplex_optimization_routine.m
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@ -1,17 +1,17 @@
function [x,fval,exitflag] = simplex_optimization_routine(objective_function,x,options,varargin)
% Nelder-Mead like optimization routine.
% By default, we use standard values for the reflection, the expansion, the contraction and the shrink coefficients (alpha = 1, chi = 2, psi = 1 / 2 and σ = 1 / 2).
% See http://en.wikipedia.org/wiki/Nelder-Mead_method
% See http://en.wikipedia.org/wiki/Nelder-Mead_method
%
% This routine uses the Nelder-Mead simplex (direct search) method.
% As chaining could reveal interesting to reach the solution neighborhood,
% the function automatically restarts from the current solution while
% amelioration is possible.
% This routine uses the Nelder-Mead simplex (direct search) method.
% As chaining could reveal interesting to reach the solution neighborhood,
% the function automatically restarts from the current solution while
% amelioration is possible.
%
% INPUTS
% objective_function [string] Name of the iobjective function to be minimized.
% x [double] n*1 vector, starting guess of the optimization routine.
% options [structure]
% options [structure]
%
% OUTPUTS
%
@ -42,14 +42,14 @@ verbose = 2;
number_of_variables = length(x);
% Set tolerance parameter.
if isfield(options,'tolerance') && isfield(options.tolerance,'x')
if isfield(options,'tolerance') && isfield(options.tolerance,'x')
x_tolerance = options.tolerance.x;
else
x_tolerance = 1e-4;
end
% Set tolerance parameter.
if isfield(options,'tolerance') && isfield(options.tolerance,'f')
if isfield(options,'tolerance') && isfield(options.tolerance,'f')
f_tolerance = options.tolerance.f;
else
f_tolerance = 1e-4;
@ -157,7 +157,7 @@ zero_delta = delta/200;% To be used instead of delta if x(i) is zero.
if isfield(options,'max_no_improvements')
max_no_improvements = options.max_no_improvements;
else
max_no_improvements = number_of_variables*10;
max_no_improvements = number_of_variables*10;
end
% Set vector of indices.
@ -331,7 +331,7 @@ while (func_count < max_func_calls) && (iter_count < max_iterations) && (simplex
else% xr is not better than previous point v(:,n).
if fxr < fv(end)% xr is better than previous worst point [=> outside contraction].
xc = (1 + psi*rho)*xbar - psi*rho*v(:,end);
x = xc;
x = xc;
fxc = feval(objective_function,x,varargin{:});
func_count = func_count+1;
if fxc <= fxr
@ -343,7 +343,7 @@ while (func_count < max_func_calls) && (iter_count < max_iterations) && (simplex
end
else% xr is the worst point [=> inside contraction].
xcc = (1-psi)*xbar + psi*v(:,end);
x = xcc;
x = xcc;
fxcc = feval(objective_function,x,varargin{:});
func_count = func_count+1;
if fxcc < fv(end)