require "table2"
local fmt = require "fmt"

local function fivenum(a)
    a:sort()
    local n5 = table.rep(5, 0)
    local n = #a
    local n4 = ((n + 3) // 2) / 2
    local d = {1, n4, (n + 1) / 2, n + 1 - n4, n}
    local e = 0
    for d as de do
        local floor = math.floor(de - 1)
        local ceil  = math.ceil(de - 1)
        n5[e + 1] = 0.5 * (a[floor + 1] + a[ceil + 1])
        e += 1
    end
    return n5
end

local x1 = {36, 40, 7, 39, 41, 15}
local x2 = {15, 6, 42, 41, 7, 36, 49, 40, 39, 47, 43}
local x3 = {
    0.14082834,  0.09748790,  1.73131507,  0.87636009, -1.95059594,
    0.73438555, -0.03035726,  1.46675970, -0.74621349, -0.72588772,
    0.63905160,  0.61501527, -0.98983780, -1.00447874, -0.62759469,
    0.66206163,  1.04312009, -0.10305385,  0.75775634,  0.32566578
}
for {x1, x2, x3} as x do fmt.lprint(fivenum(x)) end