function?[tx_newf_newg_newfunEvalsH]?=?ArmijoBacktrack（...
????xtdffrggtdc1LStolXdebugdoPlotsaveHessianCompfunObjvarargin）
%
%?Backtracking?linesearch?to?satisfy?Armijo?condition
%
%?Inputs:
%???x:?starting?location
%???t:?initial?step?size
%???d:?descent?direction
%???f:?function?value?at?starting?location
%???fr:?reference?function?value?（usually?funObj（x））
%???gtd:?directional?derivative?at?starting?location
%???c1:?sufficient?decrease?parameter
%???debug:?display?debugging?information
%???LS:?type?of?interpolation
%???tolX:?minimum?allowable?step?length
%???doPlot:?do?a?graphical?display?of?interpolation
%???funObj:?objective?function
%???varargin:?parameters?of?objective?function
%
%?Outputs:
%???t:?step?length
%???f_new:?function?value?at?x+t*d
%???g_new:?gradient?value?at?x+t*d
%???funEvals:?number?function?evaluations?performed?by?line?search
%???H:?Hessian?at?initial?guess?（only?computed?if?requested

%?Evaluate?the?objective?and?Gradient?at?the?Initial?Step
if?nargout?==?6
????[f_newg_newH]?=?feval（funObj?x?+?t*d?varargin{:}）;?
else
????[f_newg_new]?=?feval（funObj?x?+?t*d?varargin{:}）;?
end
funEvals?=?1;

while?f_new?>?fr?+?c1*t*gtd?||?~isLegal（f_new）

????temp?=?t;
????if?LS?==?0?||?~isLegal（f_new）
????????%?Backtrack?w/?fixed?backtracking?rate
????????if?debug
????????????fprintf（‘Fixed?BT\n‘）;
????????end
????????t?=?0.5*t;
????elseif?LS?==?2?&&?isLegal（g_new）
????????%?Backtracking?w/?cubic?interpolation?w/?derivative
????????if?debug
????????????fprintf（‘Grad-Cubic?BT\n‘）;
????????end
????????t?=?polyinterp（[0?f?gtd;?t?f_new?g_new‘*d]doPlot）;
????elseif?funEvals?????????%?Backtracking?w/?quadratic?interpolation?（no?derivative?at?new?point）
????????if?debug
????????????fprintf（‘Quad?BT\n‘）;
????????end
????????t?=?polyinterp（[0?f?gtd;?t?f_new?sqrt（-1）]doPlot）;
????else%if?LS?==?1
????????%?Backtracking?w/?cubic?interpolation?（no?derivatives?at?new?points）
????????if?debug
????????????fprintf（‘Cubic?BT\n‘）;
????????end
????????t?=?polyinterp（[0?f?gtd;?t?f_new?sqrt（-1）;?t_prev?f_prev?sqrt（-1）]doPlot）;
????end

????%?Adjust?if?change?in?t?is?too?small/large

????if?t?????????if?debug
????????????fprintf（‘Interpolated?Value?Too?Small?Adjusting\n‘）;
????????end
????????t?=?temp*1e-3;
????elseif?t?>?temp*0.6
????????if?debug
????????????fprintf（‘Interpolated?Value?Too?Large?Adjusting\n‘）;
????????end
????????t?=?temp*0.6;
????end

????f_prev?=?f_new;
????t_prev?=?temp;
????if?~saveHessianComp?&&?nargout?==?6
????????[f_newg_newH]?=?feval（funObj?x?+?t*d?varargin{:}）;?
????else
????????[f_newg_new]?=?feval（funObj?x?+?t*d?varargin{:}）;?
????end
????funEvals?=?funEvals+1;

????%?Check?whether?step?size?has?become?too?small
????if?sum（abs（t*d））?<=?tolX
????????if?debug
????????????fprintf（‘Backtracking?Line?Search?Failed\n‘）;
????????end
????????t?=?0;
????????f_new?=?f;
???????

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----

?????文件???????3251??2011-01-03?21:39??minFunc\ArmijoBacktrack.m

?????文件????????807??2011-01-03?21:39??minFunc\autoGrad.m

?????文件????????901??2011-01-03?21:39??minFunc\autoHess.m

?????文件????????317??2011-01-03?21:39??minFunc\autoHv.m

?????文件????????870??2011-01-03?21:39??minFunc\autoTensor.m

?????文件????????385??2011-01-03?21:39??minFunc\callOutput.m

?????文件???????1845??2011-01-03?21:39??minFunc\conjGrad.m

?????文件????????995??2011-01-03?21:39??minFunc\dampedUpdate.m

?????文件???????2421??2011-01-03?21:39??minFunc\example_minFunc.m

?????文件???????1604??2011-01-03?21:39??minFunc\example_minFunc_LR.m

?????文件????????107??2011-01-03?21:39??minFunc\isLegal.m

?????文件????????924??2011-01-03?21:39??minFunc\lbfgs.m

?????文件???????2408??2011-01-03?21:39??minFunc\lbfgsC.c

?????文件???????7707??2011-01-03?21:39??minFunc\lbfgsC.mexa64

?????文件???????7733??2011-01-03?21:39??minFunc\lbfgsC.mexglx

?????文件???????9500??2011-01-03?21:39??minFunc\lbfgsC.mexmac

?????文件??????12660??2011-01-03?21:39??minFunc\lbfgsC.mexmaci

?????文件???????8800??2011-01-03?21:39??minFunc\lbfgsC.mexmaci64

?????文件???????7168??2011-01-03?21:39??minFunc\lbfgsC.mexw32

?????文件???????9728??2011-01-03?21:39??minFunc\lbfgsC.mexw64

?????文件????????614??2011-01-03?21:39??minFunc\lbfgsUpdate.m

?????文件????????417??2011-01-03?21:39??minFunc\logistic\LogisticDiagPrecond.m

?????文件????????216??2011-01-03?21:39??minFunc\logistic\LogisticHv.m

?????文件????????659??2011-01-03?21:39??minFunc\logistic\LogisticLoss.m

?????文件???????1154??2011-01-03?21:39??minFunc\logistic\mexutil.c

?????文件????????317??2011-01-03?21:39??minFunc\logistic\mexutil.h

?????文件????????227??2011-01-03?21:39??minFunc\logistic\mylogsumexp.m

?????文件???????3965??2011-01-03?21:39??minFunc\logistic\repmatC.c

?????文件???????7680??2011-01-03?21:39??minFunc\logistic\repmatC.dll

?????文件??????20682??2011-01-03?21:39??minFunc\logistic\repmatC.mexglx

............此處省略21個文件信息