(*^

::[	frontEndVersion = "Macintosh Mathematica Notebook Front End Version 2.1";
	macintoshStandardFontEncoding; 
	paletteColors = 128; automaticGrouping; currentKernel; 
	fontset = title, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeTitle, center, M7, bold, e8,  24, "Times"; ;
	fontset = subtitle, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeTitle, center, M7, bold, e6,  18, "Times"; ;
	fontset = subsubtitle, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeTitle, center, M7, italic, e6,  14, "Times"; ;
	fontset = section, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeSection, grayBox, M22, bold, a20,  18, "Times"; ;
	fontset = subsection, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeSection, blackBox, M19, bold, a15,  14, "Times"; ;
	fontset = subsubsection, inactive, noPageBreakBelow, nohscroll, preserveAspect, groupLikeSection, whiteBox, M18, bold, a12,  12, "Times"; ;
	fontset = text, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = smalltext, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  10, "Times"; ;
	fontset = input, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeInput, M42, N23, bold, L-5,  12, "Courier"; ;
	fontset = output, output, inactive, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeOutput, M42, N23, L-5,  12, "Courier"; ;
	fontset = message, inactive, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeOutput, M42, N23, R65535, L-5,  12, "Courier"; ;
	fontset = print, inactive, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeOutput, M42, N23, L-5,  12, "Courier"; ;
	fontset = info, inactive, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeOutput, M42, N23, B65535, L-5,  12, "Courier"; ;
	fontset = postscript, PostScript, formatAsPostScript, output, inactive, noPageBreakInGroup, nowordwrap, preserveAspect, groupLikeGraphics, M7, l34, w282, h287,  12, "Courier"; ;
	fontset = name, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7, italic,  10, "Geneva"; ;
	fontset = header, inactive, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = leftheader, inactive, L2,  12, "Times"; ;
	fontset = footer, inactive, noKeepOnOnePage, preserveAspect, center, M7,  12, "Times"; ;
	fontset = leftfooter, inactive, L2,  12, "Times"; ;
	fontset = help, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  10, "Times"; ;
	fontset = clipboard, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = completions, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = special1, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = special2, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = special3, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = special4, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
	fontset = special5, inactive, nohscroll, noKeepOnOnePage, preserveAspect, M7,  12, "Times"; ;
]
:[font = special1; inactive; preserveAspect; ]
                         "R" BL, VRBL and GRBL -- Mathematica  Lab

The cell below sets up the parameters for the model simulated using the TI-92 in this module.  Evaluate it now.
;[s]
6:0,1;50,2;61,1;66,0;163,3;178,0;180,-1;
4:2,13,9,Times,0,12,0,0,0;2,13,9,Times,1,12,0,0,0;1,13,9,Times,3,12,0,0,0;1,13,9,Times,1,12,65535,0,0;
:[font = input; preserveAspect; ]
Clear[n, t, p, k, d]

n = 30;                   (*    Duration               *)

t = Table[0, {i, 1, n}];  (* Transmission Probabilties *)

t[[1]] = 0.25;
t[[2]] = 0.25;
t[[3]] = 0.25;
t[[4]] = 0.25;

p = 50;                   (* Number of People          *)

k = 2;                    (* Contacts per Person       *)

d = 7;                    (* Length of Cold            *)
:[font = special1; inactive; preserveAspect; ]
The cell below defines a procedure  Cold  that simulates the model and draws graphs showing the result.  Evaluate the next cell now to define this procedure.  
;[s]
5:0,0;35,1;40,0;105,2;156,0;160,-1;
3:3,13,9,Times,0,12,0,0,0;1,13,9,Times,1,12,0,0,0;1,13,9,Times,1,12,65535,0,0;
:[font = input; preserveAspect; ]
Cold[] := Block[
 {q, i, j, v, w, newi, news, newr,
  ilist, slist, rlist, infected, susceptible, recovered},
 Clear[q];
 q = Table[0, {i, 1, p}];
 For[i = 1, i <= 5, i = i + 1,
     v = Random[Integer, {1, p}];
     While[q[[v]] > 0, v = Random[Integer, {1, p}]];
     q[[v]] = 1;
    ];
 slist = {{0, p - 5}};
 ilist = {{0, 5}};
 rlist = {{0, 0}};
 For[w = 1, w <= n, w = w + 1,
     For[v = 1, v <= p, v = v + 1,
         If[q[[v]] == 0,
            For[j = 1, j <= k, j = j + 1,
                i = Random[Integer, {1, p}];
                If[(q[[i]] > 0) && (Random[] < t[[q[[i]]]]),
                   q[[v]] = 1]
               ]
           ]
        ];
     newr = 0;
     news = 0;
     For[j = 1, j <= p, j = j + 1,
         If[q[[j]] == 0, news = news + 1,
            If[q[[j]] > d, newr = newr + 1]
           ]
        ];
     newi = p - news - newr;
     slist = Join[slist, {{w, news}}];
     ilist = Join[ilist, {{w, newi}}];
     rlist = Join[rlist, {{w, newr}}];
     For[i = 1, i <= p, i = i + 1,
         If[q[[i]] > 0, q[[i]] = q[[i]] + 1];
        ];
    ];
 infected = ListPlot[ilist, PlotJoined -> True,
                     DisplayFunction -> Identity,
                     PlotStyle -> {RGBColor[1, 0, 0]}];
 recovered = ListPlot[rlist, PlotJoined -> True,
                     DisplayFunction -> Identity,
                     PlotStyle -> {RGBColor[0, 0, 1]}];
 susceptible = ListPlot[slist, PlotJoined -> True,
                     DisplayFunction -> Identity,
                     PlotStyle -> {RGBColor[0, 0, 0]}];
 Show[{infected, recovered, susceptible},
                     DisplayFunction -> $DisplayFunction]                                       
]
   
:[font = special1; inactive; preserveAspect; ]
The next cell does one simulation of the same model done in the browser window using the TI-92.  Evaluate it now.  You can do additional simulations exactly the same way, changing the various parameters in the model as appropriate.  
;[s]
3:0,0;97,1;112,0;234,-1;
2:2,13,9,Times,0,12,0,0,0;1,13,9,Times,1,12,65535,0,0;
:[font = input; preserveAspect; ]
Cold[]
^*)