print text

--[[Settings]]--
local text =
    {
    "line1",
    "line2",
    "line3"
    }
local monitorSide = "top"
local textScale = 1

--[[Variables & peripherals]]--
monitor = peripheral.wrap(monitorSide)

--[[Functions]]--
local function round(number)
    return math.floor(number + 0.5)
end

--[[Main program]]--
monitor.clear()

local width, height = monitor.getSize()
monitor.setTextScale(textScale)
local yPos = round(height / 2 - #text / 2)

for i, textLine in pairs(text) do
    print(textLine)
    local xPos = round(width / 2 - #textLine / 2)
    monitor.setCursorPos(xPos, yPos + i)
    monitor.write(textLine)
end