Linear virus

turtles-own [ infected day-became-ill]
globals [ number-infected infected-set]

to go
  count-infected-turtles
  if number-infected >= Number-Of-Students [ stop ]
  infect-students
  tick
end 

to count-infected-turtles
  set number-infected count turtles with [ infected = true ]
end 

to infect-students
  let number-to-be-infected 0
  if Model = "default" [ set Model 1 ]
  if Model = 1 [
    set Daily-Infection-Rate 1
    repeat Daily-Infection-Rate [
      if number-infected < Number-Of-Students[
        ask one-of turtles with [ infected = false  ][
          set infected true
          set shape "face sad"
          set color red
          set ycor ycor * -1
          set day-became-ill ticks
          count-infected-turtles
        ]
      ]
    ]
  ]
   if Model = 2 [               ;; make this one exponential
    set Daily-Infection-Rate 1.1
    set number-to-be-infected ( number-infected * (Daily-Infection-Rate ^ ticks)  )
    set number-to-be-infected (number-to-be-infected - number-infected )
    print number-to-be-infected
    repeat number-to-be-infected [
      if number-infected < Number-Of-Students[
        ask one-of turtles with [ infected = false  ][
          set infected true
          set shape "face sad"
          set color red
          set ycor ycor * -1
          count-infected-turtles
        ]
      ]
    ]
  ]
   if Model = 3 [
    set Daily-Infection-Rate 2
    set number-to-be-infected (ticks ^ Daily-Infection-Rate )
    set number-to-be-infected (number-to-be-infected - number-infected )
    repeat number-to-be-infected[
      if number-infected < Number-Of-Students[
        ask one-of turtles with [ infected = false  ][
          set infected true
          set shape "face sad"
          set color red
          set ycor ycor * -1
          count-infected-turtles
        ]
      ]
    ]
  ]
end 

to reset
  clear-all
  setup-patches
  setup-turtles
  reset-ticks
end 

to setup-turtles
  create-turtles Number-Of-Students
  ask turtles [ setxy random-xcor random max-pycor]
  ask turtles [ if ycor = 0 [ set ycor ycor + 1 ] ]
  ask turtles [ set shape "face happy" ]
  ask turtles [ set color green ]
  ask turtles [ set infected false ]
  ask turtle 1 [ set color red ]
  ask turtle 1 [ set infected true ]
  ask turtle 1 [ set shape "face sad" ]
  ask turtle 1 [ set day-became-ill 0 ]
  let negYcor [ycor] of turtle 1
  ask turtle 1 [ set ycor ycor * -1 ]
  count-infected-turtles
end 

to setup-patches
  ask patches [ if pycor = 0 [set pcolor grey ] ]
  ask patches [ if pycor > 0 [set pcolor green + 4 ] ]
  ask patches [ if pycor < 0 [set pcolor red + 4 ] ]
end