【入门夯实】时序存储：在线人数的按分钟留痕

local onlineNow = 0
local function onPlayerEnter()
    onlineNow = onlineNow + 1
end

local series = {}
local lastMinute = -1
local function tickOnline(count)
    local minute = math.floor(os.time() / 60)
    if minute ~= lastMinute then
        lastMinute = minute
        series[#series + 1] = { m = minute, n = count }
    end
end
local function queryRange(fromTs, toTs)
    local fromM = math.floor(fromTs / 60)
    local toM = math.floor(toTs / 60)
    local out = {}
    for _, p in ipairs(series) do
        if p.m >= fromM and p.m <= toM then
            out[#out + 1] = p
        end
    end
    return out
end

local pts = queryRange(os.time() - 86400, os.time())
for _, p in ipairs(pts) do
    print(os.date("%H:%M", p.m * 60) .. "  " .. p.n .. " 人在线")
end

local function downsample(series, groupMin)
    local out = {}
    for i = 1, #series, groupMin do
        local sum, cnt = 0, 0
        for j = i, math.min(i + groupMin - 1, #series) do
            sum = sum + series[j].n
            cnt = cnt + 1
        end
        out[#out + 1] = { m = series[i].m, n = sum / cnt }
    end
    return out
end