forward
Convenience function to compute the result of the forward operator (contrast-to-measurement operator) on the contrast q, i.e. the scattered field evaluated at the receivers' positions.
Contents
Syntax
[FFqMeas,FFqROI,seti] = forward() [FFqMeas,FFqROI,seti] = forward(seti,qROI)
Description
[FFqMeas,FFqROI,seti] = forward() and [FFqMeas,FFqROI,seti] = forward(seti,qROI) compute the result of the forward operator.
If there are no input arguments, some default values are used.
Example
Example 1
[FFqMeas,FFqROI,seti] = forward(); figure(101); imagesc(real(seti.G(FFqROI(:,1)))); axis xy; axis square; figure(102); imagesc(real(FFqMeas)); axis xy; axis square;
Example 2
init; seti = struct; seti = setGeomSim(seti); qROI = seti.qROIexact; [FFqMeas,FFqROI,seti] = forward(seti,qROI); figure(101); imagesc(real(seti.G(FFqROI(:,1)))); axis xy; axis square; figure(102); imagesc(real(FFqMeas)); axis xy; axis square;
Input Arguments
- seti : struct as described in mimo.html
- qROI : contrast in ROI (region of interest) (matrix as vector of size seti.nROI^seti.dim x 1)
Output Arguments
- FFqMeas : result of forward operator, i.e. the scattered field evaluated on receivers' positions (measurements)
- FFqROI : scattered field evaluated on ROI (region of interest) stored as vector for each transmitter (complex matrix of size seti.nROI^seti.dim x seti.incNb)
- seti : struct with settings (interesting if forward() is called without input arguments)
Best Practice
This is a convenience function. To avoid unnecessary calls, use mimo.html, e.g.
[FFqMeas,~,FFqROI] = mimo(seti,qROI,'simo')
More About
The forward operator is
Read also mimo.html.
See Also
Code
function [FFqMeas,FFqROI,seti] = forward(varargin)
Preparations for mimo
if nargin == 0 init; if ~exist('seti','var') seti = struct; end seti = setGeomSim(seti); qROI = seti.qROIexact; elseif nargin == 2 seti = varargin{1}; % seti... see abvoe qROI = varargin{2}; % contrast q on ROI as a vector e.g. 8281 x 1 if size(qROI,1) ~= seti.nROI^seti.dim || size(qROI,2) ~= 1 error('Make sure that dimension of input qROI is seti.nROI^seti.dim x 1.') end else error('Function "forward" needs 0 or 2 input arguments.') end
Call of mimo
[FFqMeas,~,FFqROI] = mimo(seti, qROI, 'simo');
end