CALC_JACOBIAN_BKGND: calculate background image around
which initial estimate of jacobian is calculated
img_bkgnd = calc_jacobian_bkgnd( inv_model )
inv_model is an EIDORS fwd_model
img_bkgnd is an EIDORS struct
Usage:
The background for calc_jacobian may be specified
as an estimated value
inv_model.jacobian_bkgnd.value; % scalar OR
% vector of Nx1
Usage:
The background may be calculated by a function
inv_model.jacobian_bkgnd.func;0001 function img_bkgnd = calc_jacobian_bkgnd( inv_model ) 0002 % CALC_JACOBIAN_BKGND: calculate background image around 0003 % which initial estimate of jacobian is calculated 0004 % 0005 % img_bkgnd = calc_jacobian_bkgnd( inv_model ) 0006 % inv_model is an EIDORS fwd_model 0007 % img_bkgnd is an EIDORS struct 0008 % 0009 % Usage: 0010 % The background for calc_jacobian may be specified 0011 % as an estimated value 0012 % inv_model.jacobian_bkgnd.value; % scalar OR 0013 % % vector of Nx1 0014 % 0015 % Usage: 0016 % The background may be calculated by a function 0017 % inv_model.jacobian_bkgnd.func; 0018 0019 % (C) 2005 Andy Adler. License: GPL version 2 or version 3 0020 % $Id: calc_jacobian_bkgnd.html 2819 2011-09-07 16:43:11Z aadler $ 0021 0022 img_bkgnd= eidors_obj('get-cache', inv_model, 'jacobian_bkgnd'); 0023 if ~isempty(img_bkgnd) 0024 eidors_msg('calc_jacobian_bkgnd: using cached value', 3); 0025 return 0026 end 0027 0028 if isfield(inv_model.jacobian_bkgnd,'func') 0029 img_bkgnd= feval( inv_model.jacobian_bkgnd.func, inv_model ); 0030 else 0031 % allow bkgnd to be scalar or vector 0032 fwd_model= inv_model.fwd_model; 0033 bkgnd = ones(size(fwd_model.elems,1),1); 0034 bkgnd(:)= inv_model.jacobian_bkgnd.value; 0035 0036 img_bkgnd= eidors_obj('image', 'homog image', ... 0037 'elem_data', bkgnd, ... 0038 'fwd_model', fwd_model ); 0039 end 0040 0041 0042 eidors_obj('set-cache', inv_model, 'jacobian_bkgnd', img_bkgnd); 0043 eidors_msg('jacobian_bkgnd: setting cached value', 3);