# inseti: example

Example of input parameters to run `start` not with default parameters.

This file uses the extended soft-shrinkage operator (via `seti.invNo = 1`) and is analogous to example.html, that uses the primal-dual algorithm (via `seti.invNo = 6`). (For the different inversion types see setInvType.html.)

Apart from `seti.tau` and `seti.nOut` the parameters of this file are not specially tuned. It is a demonstration of default values.

## Contents

- Input Parameters of struct `seti`

## Input Parameters of struct `seti`

Note that this are some, but not all input parameters.

    % -- dirname: suffix
    seti.dirSuffix = '';

    % -- setGrid
    seti.dim = 2;
    seti.rCD = 0.2;
    seti.nCD = 256;

    % -- setKernel
    seti.k = 250;
    seti.model = 'helmholtz';

    % -- setContrast
    seti.contrast = 'cornerBallSparse2D';

    % -- expSetup (set experimental set-up)
    seti.incPntsType = 'circle';
    seti.measPntsType = 'circle';
    seti.incNb = 35;
    seti.measNb = 35;
    seti.radSrc = 5;
    seti.radMeas = 5;
    seti.incType = 'pointSource';
    seti.measType = 'nearField';

    % -- reconstruction
    seti.invNo = 1; % in comparison to 6 in example.m
    seti.delta = 0.01;
    seti.physBounds = [-1,3,0,3];
    seti.alpha = 0.005; % default in the case of soft-shrinkage (without wavelets)
    seti.useDis = 1;
    seti.tau = 5; % higher than in example.m (was 1.5 until 20190321, i.e. smaller than in example.m)
    seti.nOut = 500; % shrinkage needs a lot more iterations than primal-dual algorithm (was 5000 until 20190321)

    % -- reconstruction with shrinkage
    % In comparison to primal-dual algorithm it is possible to set a step size
    % by Barzilai-Borwein and a step size refinement by Armijo rule.
    % A description is in minShrink.m
    % It is recommended leaving Barzilai-Borwein and Armijo rule off.
    seti.stepsizeStart = 1;
    seti.useBarBor = 0;
    seti.useArmijo = 0;