function y0 = epi1initial(t)

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%  function y0 = epi1initial(t)                          %
%  Solution to CSE Your Homework Assignment Project 6    %
%  More Models of Infection: It's Epidemic               %
%  epi1initial.m Dianne P. O'Leary   11/03               %
%                                                        %
%  This program evaluates y(t) for t <= 0 for the        %
%  ODE of Problem 1, the DAE of Problem 2, and the       %
%  DDE of Problem 3.                                     %
%  The y vector has 3 components:                        %
%        infected, susceptible, and recovered.           %
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

global mytrans myrecov myinitinfec 

% Construct the initial conditions.

if (t < 0)
   inf = 0;
else
   inf = myinitinfec;
end

y0 = [inf;1-inf;0];