Infection Dynamic Model (Model Definition GUI)
This page shows how to prepare the Infection Dynamic Model in the Graphical User interface of COSSAN-X.
Contents
Input
Suppose to consider a small village with an initial population of 1000 individuals.
Parameter
In the GUI a parameters object named S0 is defined with a values = 1000 as shown in the figure:
Random Variables
Four Random Variable object are used to model different parameter of the Infection model. More specifically 3 random variables with uniformly distributed between 0 and 1 are used to model the infection coefficient, the recovery rate and the death rate respectively. The contact coefficient is modelled using a beta distribution with parameter 2 and 7.
Evaluator
A Matlab script is then used to model the infection spread coefficient (Y).
Matlab script (Single Array I/O)
In this example we use single array for the Input / Output interaction.
Order of the input factors The order of the input factors defined in the Matlab script is important when Single Array is used |
The following matlab script is used to model the infection spread coefficient.
% INPUT % S0 if the first column of the matrix Minput % gamma is the second column of the matrix Minput % kappa is the third column of the matrix Minput % r is the forth column of the matrix Minput % delta is the fifth column of the matrix Minput % OUTPUT % We have only 1 output that is the column of the matrix Moutput % Y = gamma.*kappa.*Szero-r-delta; Moutput=Minput(:,2).* Minput(:,3).* Minput(:,1)-Minput(:,4) - Minput(:,5); % The .* means Element-by-element multiplication
Matlab script (Structure I/O)
Alternative a Matlab script where the Input and Output are passes as a structure can be used. It is necessary to select the appropriate Matlab I/O type as shown below.
The Matlab script used is:
% Matlab Script Template % ========================================================================= % COSSAN working group, % E: info@cossan.co.uk % W: www.cossan.co.uk % Copyright 1993-2016 % ========================================================================= % Cycle over realizations (samples) % % DO NOT REMOVE THIS CYCLE for n= 1:length(Tinput) % Insert your code here % Example: Toutput(n).Y= Tinput(n).gamma*Tinput(n).kappa*Tinput(n).S0-Tinput(n).r-Tinput(n).delta; end
Model
Finally a Physical Model is defined in the GUI. This can be easily created by adding the modelInfection evaluator to the Physical Model (i.e. using the + button in the evaluator section of the Physical Model editor).