initial commit

This commit is contained in:
2026-08-07 15:56:42 +09:00
commit 91ad25aca9
1012 changed files with 159314 additions and 0 deletions
+97
View File
@@ -0,0 +1,97 @@
function [a,f] = brent(func,x0,dx,a1,a,a2,f1,f,f2,varargin)
% one-dimensional minimization by parabolic interpolation & golden
% section (does not use the gradient)
%
% [a,f] = brent(func,x0,dx,a1,a,a2,f1,f,f2,varargin)
%
% func = string name of objective function
% x0 = starting point of linesearch
% dx = direction of linesearch
% a1,a,a2 = bracketing triplet of steplengths (a1<a<a2)
% f1,f,f2 = objective function at steplengths a1, a, & a2
% a = output as final steplength
% f = output as objective function at final steplength
gold = 0.3819660; % golden ratio
itmax = 5;
tol = 0.5;
% check order of bracket
if (a1>a)|(a2<a), error('brent called with bracket in wrong order'), end
% initialize
v = a;fv = f; % middle point on step before last
w = a;fw = f; % middle point on last step
e = 0; % distance moved on step before last
% iterations
for it = 1:itmax
am = 0.5*(a1+a2);
tol1 = tol*abs(a)+eps;
tol2 = 2*tol1;
% test for convergence
if abs(a-am)<=(tol2-0.5*(a2-a1)), return, end
% choose next point
if abs(e)>tol1 % construct a trial parabolic fit
r = (a-w)*(f-fv);
q = (a-v)*(f-fw);
p = (a-v)*q-(a-w)*r;
q = 2*(q-r);
if q>0, p = -p; end
q = abs(q);
etemp = e;
e = d;
% check acceptability of parabolic fit
ok = ~(abs(p)>=abs(0.5*q*etemp) | p<=q*(a1-a) | p>=q*(a2-a));
if ok % take parabolic step
d = p/q;
u = a+d;
if (u-a1)<tol2 | (a2-u)<tol2, d = sign(am-a)*tol1; end
else % take golden section step
if a>=am
e = a1-a;
else
e = a2-a;
end
d = gold*e;
end
else % take golden section step
if a>=am
e = a1-a;
else
e = a2-a;
end
d = gold*e;
end
% arrive here with d computed either from
% parabolic fit or else from golden section
if abs(d)>=tol1
u = a+d;
else
u = a+sign(d)*tol1;
end
fu = feval(func,x0+u*dx,varargin{:}); % one function evaluation per iteration
if fu<=f
if u>=a
a1 = a;
else
a2 = a;
end
v = w; fv = fw;
w = a; fw = f;
a = u; f = fu;
else
if u<a
a1 = u;
else
a2 = u;
end
if fu<=fw | w==a
v = w; fv = fw;
w = u; fw = fu;
elseif fu<=fv | v==a | v==w
v = u; fv = fu;
end
end
end
disp('exceeded maximum number of iterations')
return
end
+82
View File
@@ -0,0 +1,82 @@
function [x, p] = cgmin1(func,x,itmax,ftol,xtol,varargin)
% conjugate-gradient optimization routine
% NOTE: linesearch subroutines do not use the gradient
%
% [x] = cgmin1(func,x,itmax,ftol,xtol,varargin)
%
% func = string name of objective function which returns both the
% objective function value and the gradient
% x = input as initial starting point and output as final point
% itmax = maximum number of iterations (empty for default = 50)
% ftol = relative function tolerance (empty for default = 1e-3)
% xtol = absolute solution tolerance (empty for default = 1e-3)
% varargin = extra variables required by objective function
%
% DISCLAIMER: This code is not intended for distribution. I have many
% versions of this code and am constantly revising it. I believe this
% version is working properly. However, I will not vouch for the code.
% Anyone using the code for thesis research has a responsibility to go
% through the code line-by-line and read relevant references to understand
% the code completely. In my opinion, you have two options if you want to
% publish results obtained with the code: (i) go through the code line-by-
% line and read relevent references to understand how the code works and make
% sure it is working properly for your application, or (ii) I can sit down
% with you an go through this code and the additional code that you have
% written to go along with it and make sure it is working properly. Option
% (i) is preferred, and I ask that you do NOT acknowledge me in print (first,
% it would be more appropriate for you to reference "Numerical Recipes",
% and second, I prefer not to be named in a paper with which I do not have
% detailed knowledge). If you decide to go with option (ii), I would expect
% to learn the details of your research and be included in the author list.
%
% Sam Thurman, May 9, 2005
import utils.*
if isempty(itmax), itmax = 50; end
if isempty(ftol), ftol = 1e-3; end
if isempty(xtol), xtol = 1e-3; end
% loop
flg = 0; % use steepest descent for first iteration
step = 0; % to guess at initial steplength
for it = 1:itmax
% function evaluation
[f,grad,p] = feval(func,x,varargin{:});
% disp(f)
% check for feasibility
if isinf(f), error('encountered an infeasible solution'), end
if norm(grad(:))==0, return, end % done if gradient is zero (unlikely)
% pick search direction
if (flg==1) & (rem(it,25)~=0) % linesearch found a minimum -> use cg equations
gg = g(:)'*g(:);
% dgg = grad(:)'*grad(:); % this statement for Fletcher-Reeves
dgg = (grad(:)+g(:))'*grad(:); % this statement for Polak-Ribiere
ga = dgg/gg;
g = -grad;
h = g+ga*h;
dx = h/norm(h(:));
df = grad(:)'*dx(:);
end
if (flg==0) | (rem(it,25)==0) | (df>0) % revert to steepest decent
g = -grad;
h = g;
dx = h/norm(h(:));
df = grad(:)'*dx(:);
end
% initial steplength guess
if step == 0
step = max(0.001,min([1,2*abs(f/(grad(:)'*dx(:)))])); % same as fminusub.m (line 124) in optim toolbox
else % oterwise use previous steplength
step = step/10;
end
% linesearch
[x,fvalue,step,flg] = engines.ML.linesearch(func,x,f,df,dx,step,varargin{:});
% test for convergence
if (2*abs(f-fvalue)<=ftol*(abs(f)+abs(fvalue)+ftol)) & (step*norm(dx(:))<=xtol) & (it~=1) % normal return
return
end
end
verbose(3, 'Maximum number of iterations exceeded.')
return
end
+369
View File
@@ -0,0 +1,369 @@
% Main code to compute error metric and gradient
% Jan 09 2013
% Academic License Agreement
%
% Source Code
%
% Introduction
% This license agreement sets forth the terms and conditions under which the PAUL SCHERRER INSTITUT (PSI), CH-5232 Villigen-PSI, Switzerland (hereafter "LICENSOR")
% will grant you (hereafter "LICENSEE") a royalty-free, non-exclusive license for academic, non-commercial purposes only (hereafter "LICENSE") to use the cSAXS
% ptychography MATLAB package computer software program and associated documentation furnished hereunder (hereafter "PROGRAM").
%
% Terms and Conditions of the LICENSE
% 1. LICENSOR grants to LICENSEE a royalty-free, non-exclusive license to use the PROGRAM for academic, non-commercial purposes, upon the terms and conditions
% hereinafter set out and until termination of this license as set forth below.
% 2. LICENSEE acknowledges that the PROGRAM is a research tool still in the development stage. The PROGRAM is provided without any related services, improvements
% or warranties from LICENSOR and that the LICENSE is entered into in order to enable others to utilize the PROGRAM in their academic activities. It is the
% LICENSEEs responsibility to ensure its proper use and the correctness of the results.
% 3. THE PROGRAM IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR
% A PARTICULAR PURPOSE AND NONINFRINGEMENT OF ANY PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS. IN NO EVENT SHALL THE LICENSOR, THE AUTHORS OR THE COPYRIGHT
% HOLDERS BE LIABLE FOR ANY CLAIM, DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES OR OTHER LIABILITY ARISING FROM, OUT OF OR IN CONNECTION WITH THE PROGRAM OR THE USE
% OF THE PROGRAM OR OTHER DEALINGS IN THE PROGRAM.
% 4. LICENSEE agrees that it will use the PROGRAM and any modifications, improvements, or derivatives of PROGRAM that LICENSEE may create (collectively,
% "IMPROVEMENTS") solely for academic, non-commercial purposes and that any copy of PROGRAM or derivatives thereof shall be distributed only under the same
% license as PROGRAM. The terms "academic, non-commercial", as used in this Agreement, mean academic or other scholarly research which (a) is not undertaken for
% profit, or (b) is not intended to produce works, services, or data for commercial use, or (c) is neither conducted, nor funded, by a person or an entity engaged
% in the commercial use, application or exploitation of works similar to the PROGRAM.
% 5. LICENSEE agrees that it shall make the following acknowledgement in any publication resulting from the use of the PROGRAM or any translation of the code into
% another computing language:
% "Data processing was carried out using the cSAXS ptychography MATLAB package developed by the Science IT and the coherent X-ray scattering (CXS) groups, Paul
% Scherrer Institut, Switzerland."
%
% Additionally, any publication using the package, or any translation of the code into another computing language should cite for difference map:
% P. Thibault, M. Dierolf, A. Menzel, O. Bunk, C. David, F. Pfeiffer, High-resolution scanning X-ray diffraction microscopy, Science 321, 379382 (2008).
% (doi: 10.1126/science.1158573),
% for maximum likelihood:
% P. Thibault and M. Guizar-Sicairos, Maximum-likelihood refinement for coherent diffractive imaging, New J. Phys. 14, 063004 (2012).
% (doi: 10.1088/1367-2630/14/6/063004),
% for mixed coherent modes:
% P. Thibault and A. Menzel, Reconstructing state mixtures from diffraction measurements, Nature 494, 6871 (2013). (doi: 10.1038/nature11806),
% and/or for multislice:
% E. H. R. Tsai, I. Usov, A. Diaz, A. Menzel, and M. Guizar-Sicairos, X-ray ptychography with extended depth of field, Opt. Express 24, 2908929108 (2016).
% (doi: 10.1364/OE.24.029089).
% 6. Except for the above-mentioned acknowledgment, LICENSEE shall not use the PROGRAM title or the names or logos of LICENSOR, nor any adaptation thereof, nor the
% names of any of its employees or laboratories, in any advertising, promotional or sales material without prior written consent obtained from LICENSOR in each case.
% 7. Ownership of all rights, including copyright in the PROGRAM and in any material associated therewith, shall at all times remain with LICENSOR, and LICENSEE
% agrees to preserve same. LICENSEE agrees not to use any portion of the PROGRAM or of any IMPROVEMENTS in any machine-readable form outside the PROGRAM, nor to
% make any copies except for its internal use, without prior written consent of LICENSOR. LICENSEE agrees to place the following copyright notice on any such copies:
% © All rights reserved. PAUL SCHERRER INSTITUT, Switzerland, Laboratory for Macromolecules and Bioimaging, 2017.
% 8. The LICENSE shall not be construed to confer any rights upon LICENSEE by implication or otherwise except as specifically set forth herein.
% 9. DISCLAIMER: LICENSEE shall be aware that Phase Focus Limited of Sheffield, UK has an international portfolio of patents and pending applications which relate
% to ptychography and that the PROGRAM may be capable of being used in circumstances which may fall within the claims of one or more of the Phase Focus patents,
% in particular of patent with international application number PCT/GB2005/001464. The LICENSOR explicitly declares not to indemnify the users of the software
% in case Phase Focus or any other third party will open a legal action against the LICENSEE due to the use of the program.
% 10. This Agreement shall be governed by the material laws of Switzerland and any dispute arising out of this Agreement or use of the PROGRAM shall be brought before
% the courts of Zürich, Switzerland.
function [func, grad, p] = gradient_ptycho(xopt,p,fmag2, initialerror,fnorm,creg,smooth_gradient)
import utils.verbose
%%% Initialize variables %%%
func = 0; % Should be zero except for poisson (factorial factor)
for ii = 1:p.numobjs
grado{ii} = zeros([p.object_size(ii,:) p.object_modes], 'like', xopt)+1i*eps;
end
gradp = zeros(p.asize(1),p.asize(2),p.numprobs,p.probe_modes, 'like', xopt)+1i*eps;
% gradx = zeros(n,1);
% grady = zeros(n,1);
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% Arrange optimization variables %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if p.opt_flags(1) == 1,
for obnum = 1:p.numobjs
% ob{obnum} = reshape(xopt(1:p.object_size(obnum,1)*p.object_size(obnum,2)),...
% p.object_size(obnum,1),p.object_size(obnum,2)) + ...
% 1i*reshape(xopt(p.object_size(obnum,1)*p.object_size(obnum,2)+1:2*p.object_size(obnum,1)*p.object_size(obnum,2)),...
% p.object_size(obnum,1),p.object_size(obnum,2));
ob{obnum} = reshape(xopt(1:numel(grado{obnum})),...
size(grado{obnum})) + ...
1i*reshape(xopt(numel(grado{obnum})+1:2*numel(grado{obnum})),...
size(grado{obnum}));
xopt = xopt(2*numel(grado{obnum})+1:end);
end
end
if p.opt_flags(2) == 1,
probes = reshape(xopt(1:numel(gradp)),size(gradp)) + ...
1i*reshape(xopt(numel(gradp)+1:2*numel(gradp)),size(gradp));
xopt = xopt(2*numel(gradp)+1:end);
end
% if flags(3) == 1,
% x = tmp(1:params.n);
% y = tmp(params.n+1:2*params.n);
% end
%%%%%%%%%%%%%%%%%%%%%
%%% Support error %%%
%%%%%%%%%%%%%%%%%%%%%
% Option to add later for a smooth support constraint error
%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% Compute error metric %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% Still to implement here:
% + L1 and L2 metrics
% + Insensitive to multiplicative scale
if nargout > 1
verbose(3,'Computing gradient')
end
for ii = 1:p.numscans
prnum = p.share_probe_ID(ii);
obnum = p.share_object_ID(ii);
probe = probes(:,:,prnum,:);
Iq_all = 0;
for obmode = 1:p.object_modes
obj_proj{obmode} = core.get_projections(p, ob{obnum}(:,:,obmode), ii);
psiq_all{obmode} = fft2(bsxfun(@times,obj_proj{obmode},probe/fnorm)); % view in Fourier domain
Iq_all = Iq_all + sum(abs(psiq_all{obmode}).^2,4);
end
% Use implicit matlab paralelization to avoid computational overhead ,
% currenly implemented only for L1 norm
if strcmpi(p.opt_errmetric,'l1')
fmag = p.fmag(:,:,p.scanidxs{ii});
fmask = p.fmask(:,:,p.scanidxs{ii});
Fq = sqrt(Iq_all);
%%% Invariant to intensity fluctuations
if p.inv_intensity
alpha = sum(sum(fmask.*fmag.*Fq))./sum(sum(fmag.*Fq.^2));
else
alpha = 1;
end
func = sum(sum(sum(fmask.*( alpha.*Fq - fmag ).^2)));
if nargout > 1 % Compute gradients
for obmode = 1:p.object_modes
chir = alpha.*ifft2(fmask.*( alpha - fmag./(Fq+eps) ).*psiq_all{obmode})*fnorm; % May not be needed for position optimization
if p.opt_flags(1) == 1,
grado{obnum}(:,:,obmode) = core.set_projections(p, grado{obnum}(:,:,obmode), sum(2*conj(probe).*chir,4), ii);
end
if p.opt_flags(2) == 1
gradp(:,:,prnum,:) = gradp(:,:,prnum,:) ...
+ sum(2*conj(obj_proj{obmode}).*chir,3);
end
end
end
else
for jj = p.scanidxs{ii} % Loop through diffraction patterns
Indy = round(p.positions(jj,1)) + (1:p.asize(1));
Indx = round(p.positions(jj,2)) + (1:p.asize(2));
Iq = Iq_all(:,:,jj-p.scanidxs{ii}(1)+1);
switch lower(p.opt_errmetric)
case 'poisson'
%%% Invariant to intensity fluctuations
if p.inv_intensity
% The numerator could be computed once outside
alpha = sum(sum(p.fmask(:,:,jj).*fmag2(:,:,jj)))/sum(sum(p.fmask(:,:,jj).*Iq));
else
alpha = 1;
end
func = func - sum(sum(p.fmask(:,:,jj).*( fmag2(:,:,jj).*log(alpha*Iq) - alpha*Iq )));
if nargout > 1 % Compute gradients
for obmode = 1:p.object_modes
psiq = psiq_all{obmode}(:,:,jj); % view in Fourier domain
chir = ifft2(p.fmask(:,:,jj).*( alpha - fmag2(:,:,jj)./Iq ).*psiq)*fnorm; % May not be needed for position optimization
for prmode = 1:p.probe_modes
if p.opt_flags(1) == 1
grado{obnum}(Indy,Indx,obmode) = grado{obnum}(Indy,Indx,obmode) ...
+ sum(2*conj(probe).*chir, 4);
end
if p.opt_flags(2) == 1
gradp(:,:,prnum,:) = gradp(:,:,prnum,:) ...
+ 2*conj(ob{obnum}(Indy,Indx,obmode)).*chir;
end
end
end
end
case 'l2'
%%% Invariant to intensity fluctuations
if p.inv_intensity
alpha = sum(sum(p.fmask(:,:,jj).*fmag2(:,:,jj).*Iq))/sum(sum(p.fmask(:,:,jj).*Iq.^2));
else
alpha = 1;
end
tmp = alpha*Iq - fmag2(:,:,jj);
func = func + sum(sum(p.fmask(:,:,jj).*( tmp ).^2));
if nargout > 1 % Compute gradients
for obmode = 1:p.object_modes
psiq = psiq_all{obmode}(:,:,jj); % view in Fourier domain
chir = alpha*ifft2(2*p.fmask(:,:,jj).*( tmp ).*psiq)*fnorm; % May not be needed for position optimization
if p.opt_flags(1) == 1
grado{obnum}(Indy,Indx,obmode) = grado{obnum}(Indy,Indx,obmode) ...
+ sum(2*conj(probe).*chir,4);
end
if p.opt_flags(2) == 1
gradp(:,:,prnum,:) = gradp(:,:,prnum,:) ...
+ 2*conj(ob{obnum}(Indy,Indx,obmode)).*chir;
end
end
end
case 'l1'
% %%% Invariant to intensity fluctuations
% if p.inv_intensity
% alpha = sum(sum(p.fmask(:,:,jj).*p.fmag(:,:,jj).*Fq))/sum(sum(p.fmask(:,:,jj).*Fq.^2));
% else
% alpha = 1;
% end
% func = func + sum(sum(p.fmask(:,:,jj).*( alpha*Fq - p.fmag(:,:,jj) ).^2));
% if nargout > 1 % Compute gradients
% for obmode = 1:p.object_modes
% psiq = fft2(ob{obnum}(Indy,Indx,obmode).*probes(:,:,prnum,:))/fnorm; % view in Fourier domain
% chir = alpha*ifft2(p.fmask(:,:,jj).*( alpha - p.fmag(:,:,jj)./(Fq+eps) ).*psiq)*fnorm; % May not be needed for position optimization
% if p.opt_flags(1) == 1,
% grado{obnum}(Indy,Indx,obmode) = grado{obnum}(Indy,Indx,obmode) ...
% + sum(2*conj(probes(:,:,prnum,:)).*chir,4);
% end
% if p.opt_flags(2) == 1
% gradp(:,:,prnum,:) = gradp(:,:,prnum,:) ...
% + 2*conj(ob{obnum}(Indy,Indx,obmode)).*chir;
% end
% end
% end
otherwise
error(['Error metric ' p.opt_errmetric 'is not defined'])
end
end
end
end
func = func + initialerror;
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% Sieves preconditioning %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if (any(smooth_gradient(:)) ~= 0)&&p.opt_flags(1)
for obnum = 1:p.numobjs
for obmode = 1:p.object_modes
grado{obnum}(:,:,obmode) = conv2(grado{obnum}(:,:,obmode),smooth_gradient,'same');
end
end
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% Object regularization %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Normalized regularization to avoid the reduction of object amplitudes
% with the setting of intensity invariant
if (creg > 0)&&p.opt_flags(1)
for obnum = 1:p.numobjs
for obmode = 1:p.object_modes
% Not normalized regularization
% func = func ...
% + sum(sum( abs( ob{obnum}(2:end,1:end-1) - ob{obnum}(1:end-1,1:end-1) ).^2 ...
% + abs( ob{obnum}(1:end-1,2:end) - ob{obnum}(1:end-1,1:end-1) ).^2 ));
R = sum(sum( abs( ob{obnum}(2:end,1:end-1,obmode) - ob{obnum}(1:end-1,1:end-1,obmode) ).^2 ...
+ abs( ob{obnum}(1:end-1,2:end,obmode) - ob{obnum}(1:end-1,1:end-1,obmode) ).^2 ));
norm_r = sum(sum(abs(ob{obnum}(:,:,obmode)).^2));
func = func + creg*R/norm_r;
if nargout > 1
% % Not normalized regularization
% grado{obnum}(2:end-1,2:end-1) = grado{obnum}(2:end-1,2:end-1) + 8*ob{obnum}(2:end-1,2:end-1) ...
% - 2*ob{obnum}(1:end-2,2:end-1) - 2*ob{obnum}(3:end,2:end-1) ...
% - 2*ob{obnum}(2:end-1,1:end-2) - 2*ob{obnum}(2:end-1,3:end);
grado{obnum}(2:end-1,2:end-1,obmode) = grado{obnum}(2:end-1,2:end-1,obmode) + creg*( (8+2*R/norm_r)*ob{obnum}(2:end-1,2:end-1,obmode) ...
- 2*ob{obnum}(1:end-2,2:end-1,obmode) - 2*ob{obnum}(3:end,2:end-1,obmode) ...
- 2*ob{obnum}(2:end-1,1:end-2,obmode) - 2*ob{obnum}(2:end-1,3:end,obmode));
end
end
end
end
% normalized error, err_chi close to 1 is good result for poisson noise
err_chi = 2*sqrt(func/prod(p.asize)/p.numpos/p.renorm^2);
func = double(func);
if nargout > 1
core.errorplot(err_chi);
iteration = length(core.errorplot([]));
verbose(2, 'Iteration # %d of %d', iteration, p.opt_iter);
verbose(3,['Starting linesearch, Error = ' num2str(err_chi)]),
else
verbose(3,['Error = ' num2str(err_chi)]),
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% Probe support constratint %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if p.use_probe_support&&p.opt_flags(2)
gradp = bsxfun(@times, gradp, p.probe_mask);
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% Scaling preconditioning %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
avobint = 0;
if p.scale_gradient&&p.opt_flags(2)
for ii = 1:p.numscans
if p.share_probe
avobint = avobint + sum( abs(grado{ii}(:)).^2 );
if ii == p.numscans
avobint = avobint/p.numscans;
gradp = sqrt( avobint/sum( abs(gradp(:)).^2 ) )*gradp;
end
else
gradp(:,:,ii,:) = sqrt( sum( abs(grado{ii}(:)).^2 )/sum(sum(sum( abs(gradp(:,:,ii,:)).^2 ))) )*gradp(:,:,ii,:);
end
end
end
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%% Arranging gradients vector %%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
if nargout > 1
grad = []; % Optimization vector
if p.opt_flags(1) == 1,
for obnum = 1:p.numobjs
grad = [grad; real(grado{obnum}(:)); imag(grado{obnum}(:))];
end
end
if p.opt_flags(2) == 1,
grad = [grad; real(gradp(:)); imag(gradp(:))];
end
% if flags(3) == 1,
% xopt = [xopt;x;y];
% else
% fixed.x = x;
% fixed.y = y;
% end
if isempty(grad),
error('At least one element of flags must be 1'),
end
%%%%%%%%%%%%%%%
%%% Display %%%
%%%%%%%%%%%%%%%
p.error_metric.value = core.errorplot([]);
p.error_metric.iteration = (1:size(core.errorplot([]),1));
p.error_metric.err_metric = '-LogLik';
p.error_metric.method = 'ML';
p.object = ob;
p.probes = probes;
if p.use_display
if (round(mod(iteration,p.plot.interval))==0)||(iteration==1)
p.plot.extratitlestring = sprintf(' (%dx%d) - iter %d', p.asize(2), p.asize(1), iteration);
p.flat_object_used = 0;
core.analysis.plot_results(p, 'use_display', p.use_display);
end
end
end
return
end
+135
View File
@@ -0,0 +1,135 @@
% linesearch routine (does not use the gradient)
%
% [x,f,a,flg] = linesearch(func,x0,f0,df0,dx,a,varargin)
%
% func = string name of objective function
% x0 = starting point of search
% f0 = objective function at x0
% df0 = derivative of objective function along dx at x0
% dx = direction of linesearch
% a = steplength input as guess output as taken
% x = final point of search
% f = objective function at final point
% flg = indicates how step was determined (0 for Armijo step, 1 for
% bracketing and refining a minimum)
% Academic License Agreement
%
% Source Code
%
% Introduction
% This license agreement sets forth the terms and conditions under which the PAUL SCHERRER INSTITUT (PSI), CH-5232 Villigen-PSI, Switzerland (hereafter "LICENSOR")
% will grant you (hereafter "LICENSEE") a royalty-free, non-exclusive license for academic, non-commercial purposes only (hereafter "LICENSE") to use the cSAXS
% ptychography MATLAB package computer software program and associated documentation furnished hereunder (hereafter "PROGRAM").
%
% Terms and Conditions of the LICENSE
% 1. LICENSOR grants to LICENSEE a royalty-free, non-exclusive license to use the PROGRAM for academic, non-commercial purposes, upon the terms and conditions
% hereinafter set out and until termination of this license as set forth below.
% 2. LICENSEE acknowledges that the PROGRAM is a research tool still in the development stage. The PROGRAM is provided without any related services, improvements
% or warranties from LICENSOR and that the LICENSE is entered into in order to enable others to utilize the PROGRAM in their academic activities. It is the
% LICENSEEs responsibility to ensure its proper use and the correctness of the results.
% 3. THE PROGRAM IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR
% A PARTICULAR PURPOSE AND NONINFRINGEMENT OF ANY PATENTS, COPYRIGHTS, TRADEMARKS OR OTHER RIGHTS. IN NO EVENT SHALL THE LICENSOR, THE AUTHORS OR THE COPYRIGHT
% HOLDERS BE LIABLE FOR ANY CLAIM, DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES OR OTHER LIABILITY ARISING FROM, OUT OF OR IN CONNECTION WITH THE PROGRAM OR THE USE
% OF THE PROGRAM OR OTHER DEALINGS IN THE PROGRAM.
% 4. LICENSEE agrees that it will use the PROGRAM and any modifications, improvements, or derivatives of PROGRAM that LICENSEE may create (collectively,
% "IMPROVEMENTS") solely for academic, non-commercial purposes and that any copy of PROGRAM or derivatives thereof shall be distributed only under the same
% license as PROGRAM. The terms "academic, non-commercial", as used in this Agreement, mean academic or other scholarly research which (a) is not undertaken for
% profit, or (b) is not intended to produce works, services, or data for commercial use, or (c) is neither conducted, nor funded, by a person or an entity engaged
% in the commercial use, application or exploitation of works similar to the PROGRAM.
% 5. LICENSEE agrees that it shall make the following acknowledgement in any publication resulting from the use of the PROGRAM or any translation of the code into
% another computing language:
% "Data processing was carried out using the cSAXS ptychography MATLAB package developed by the Science IT and the coherent X-ray scattering (CXS) groups, Paul
% Scherrer Institut, Switzerland."
%
% Additionally, any publication using the package, or any translation of the code into another computing language should cite for difference map:
% P. Thibault, M. Dierolf, A. Menzel, O. Bunk, C. David, F. Pfeiffer, High-resolution scanning X-ray diffraction microscopy, Science 321, 379382 (2008).
% (doi: 10.1126/science.1158573),
% for maximum likelihood:
% P. Thibault and M. Guizar-Sicairos, Maximum-likelihood refinement for coherent diffractive imaging, New J. Phys. 14, 063004 (2012).
% (doi: 10.1088/1367-2630/14/6/063004),
% for mixed coherent modes:
% P. Thibault and A. Menzel, Reconstructing state mixtures from diffraction measurements, Nature 494, 6871 (2013). (doi: 10.1038/nature11806),
% and/or for multislice:
% E. H. R. Tsai, I. Usov, A. Diaz, A. Menzel, and M. Guizar-Sicairos, X-ray ptychography with extended depth of field, Opt. Express 24, 2908929108 (2016).
% (doi: 10.1364/OE.24.029089).
% 6. Except for the above-mentioned acknowledgment, LICENSEE shall not use the PROGRAM title or the names or logos of LICENSOR, nor any adaptation thereof, nor the
% names of any of its employees or laboratories, in any advertising, promotional or sales material without prior written consent obtained from LICENSOR in each case.
% 7. Ownership of all rights, including copyright in the PROGRAM and in any material associated therewith, shall at all times remain with LICENSOR, and LICENSEE
% agrees to preserve same. LICENSEE agrees not to use any portion of the PROGRAM or of any IMPROVEMENTS in any machine-readable form outside the PROGRAM, nor to
% make any copies except for its internal use, without prior written consent of LICENSOR. LICENSEE agrees to place the following copyright notice on any such copies:
% © All rights reserved. PAUL SCHERRER INSTITUT, Switzerland, Laboratory for Macromolecules and Bioimaging, 2017.
% 8. The LICENSE shall not be construed to confer any rights upon LICENSEE by implication or otherwise except as specifically set forth herein.
% 9. DISCLAIMER: LICENSEE shall be aware that Phase Focus Limited of Sheffield, UK has an international portfolio of patents and pending applications which relate
% to ptychography and that the PROGRAM may be capable of being used in circumstances which may fall within the claims of one or more of the Phase Focus patents,
% in particular of patent with international application number PCT/GB2005/001464. The LICENSOR explicitly declares not to indemnify the users of the software
% in case Phase Focus or any other third party will open a legal action against the LICENSEE due to the use of the program.
% 10. This Agreement shall be governed by the material laws of Switzerland and any dispute arising out of this Agreement or use of the PROGRAM shall be brought before
% the courts of Zürich, Switzerland.
function [x,f,a,flg] = linesearch(func,x0,f0,df0,dx,a,varargin)
% check if descent direction
if df0>=0
warning('linesearch called w/o descent direction')
x = x0; f = f0; fcount = [0,0]; flg = 0;
return
end
% first point
a1 = 0; f1 = f0;
% try initial steplength
f = feval(func,x0+a*dx,varargin{:}); % no gradient returned
% keep track of old values & hopefully bracket a minimum
a2 = a; f2 = f;
% make sure initial step is feasible
while isinf(f)
a2 = a;
a = 0.25*a;
f = feval(func,x0+a*dx,varargin{:});
end
% decide what to do next based on Armijo condition
b = 0; % parameter in Armijo condition (>=0)
% if f does not satisfy Armijo condition (steplength may be too
% large) -> decrease steplength until Armijo is satisfied
if f>f0+a*b*df0
while f>f0+a*b*df0
if isinf(f2)||(f<=f2)
a2 = a; f2 = f;
end
a = 0.25*a; % decrease steplength
f = feval(func,x0+a*dx,varargin{:});
end
end
% arrive here with a1=a0=0 and f<f1 (at least)
tmp = 1;
while f2<=f % try doubling a2
a2 = 2*a2;
f2 = feval(func,x0+a2*dx,varargin{:});
if f2<f
a1 = a; f1 = f;
a = a2; f = f2;
end
if tmp==5; break; else tmp = tmp+1; end
end
% case where we should have a bracket, but f2 is infinite
while isinf(f2)
% disp('should have a bracket but f2 is infinite')
u = a+0.25*(a2-a); % point between a and a2
fu = feval(func,x0+u*dx,varargin{:});
if fu<f
a1 = a; f1 = f;
a = u; f = fu;
else
a2 = u; f2 = fu;
end
end
% last steps
if (f<f1)&&(f<f2)&&isfinite(f2) % bracketing successful -> refine minimum
[a,f] = engines.ML.brent(func,x0,dx,a1,a,a2,f1,f,f2,varargin{:});
flg = 1; % use conjugate gradient next loop
else % bracketing unsuccessful -> stop
flg = 0; % use steepest descent next loop
end
x = x0+a*dx;
return
end