Lua

Question

我正在将功率（瓦特）值写入文本文件以提取我可以使用的信息。

4.7
4.7
4.8
5.2
5.1
4.6
4.6
4.6

目前我有以下代码来计算平均值，但我想添加它以便它告诉我更多信息，例如最高值、最低值、最频繁值是什么，以及如果可能的话，如果记录了任何“0”值（* - 如果可能的话，最后一个值最好忽略它们..）

local ctr = 0
local sum = 0

for _ in io.lines"/www/EnergyPlug-b.txt" do
    ctr = ctr + 1
end
print(ctr)

for line in io.lines"/www/EnergyPlug-b.txt" do 
    sum = sum + line
end
print(sum)
average = sum / ctr
print(average)

我确实探索了通过第一个 io.lines 部分的 table.insert() 创建一个 Lua table，如下所示，但我不确定它有多好是？

local rows = {}
-- go over the file line by line
for line in io.lines("/www/EnergyPlug-b.txt") do
  -- if line matches ?.? then insert into table
  local value = line:match("%d%p%d") -- 1.5 
    --print(value) 
    table.insert(rows, value)
end

local arraymax = math.max(unpack(rows))
local arraymin = math.min(unpack(rows))

print (arraymax) -- ?.?
print (arraymin) -- ?.?

如果上面是 suitable，我应该如何最好地识别我在一开始提到的 items/values？

Answer 1

在第一个片段中，没有理由为 ctr 和 sum 设置单独的循环。你可以在一个循环中完成。

你剪的第二张没问题。 unpack 是有限的，因此这不适用于数千个值。

无论如何你都必须遍历 table 以获得其他值，这样你就可以在没有该大小限制的情况下确定该循环中的最小值和最大值。

local value = line:match("%d%p%d") 如果那个文件中只有那些数字你可以跳过这里的模式匹配。

计算非常直接。我不确定你在这里遇到了什么问题。

local min = math.huge -- use a value that is definitely bigger than any value
local max = -math.huge -- use a value that is definitely smaller than any value
local counts = {} -- an emtpy table we'll use to count how often each value occurs
local numIngored = 0 -- how many 0 values have we ignored?
for line in io.lines(yourFileName) do
  -- convert string to a number
  local value = tonumber(line)
  -- if we take the value into account
  if value ~= 0.0 then
    -- update min and max values
    min = value < min and value or min
    max = value > max and value or max
    -- update counts
    counts[value] = counts[value] and counts[value] + 1 or 1
  else
    -- count ignored values
    numIgnored = numIgnored + 1
  end
end

我会留给你从 counts

中获取最频繁的值

Answer 2

感谢@piglet 和使用其他 SO 帖子，这就是我最终得到的..

local min = math.huge -- use a value that is definitely bigger than any value
local max = -math.huge -- use a value that is definitely smaller than any value
local ctr = 0
local valtotal = 0
local counts = {} -- an emtpy table we'll use to count how often each value occurs
local numIngored = 0 -- how many 0 values have we ignored?
for line in io.lines("/www/EnergyPlug-b.txt") do
  -- convert string to a number
  local value = tonumber(line)
  -- if we take the value into account
  if value ~= 0.0 then
    ctr = ctr + 1
    valtotal = valtotal + value
    -- update min and max values
    min = value < min and value or min
    max = value > max and value or max
    -- update counts
    counts[value] = counts[value] and counts[value] + 1 or 1
  else
    -- count ignored values
    numIgnored = numIgnored + 1
  end
end

print("----Table print out -----")

for k, v in pairs(counts) do
    print(k,v)
end

print("---------------------------")
print("Lowest value recorded = " ..min)
print("Highest value recorded = " ..max)
print("Average value recorded = " ..round2(valtotal / ctr, 1))
print("Number of values recorded = " ..ctr)
print("---------------------------")

local max_val, key1 = -math.huge
for k, v in pairs(counts) do
    if v > max_val then 
        max_val, key1 = v, k
    end
end

local min_val, key2 = math.huge 
for k1, v1 in pairs(counts) do
    if v1 < min_val or v1 == min_val then
        min_val, key2 = v1, k1
    end
end

local min_qty, max_qty = 0, 0
local min_str, max_str = "", ""
for k2, v2 in pairs(counts) do
    if v2 == min_val then
        min_qty = min_qty + 1
        min_str = min_str .. " " .. k2
    elseif v2 == max_val then
        max_qty = max_qty + 1
        max_str = max_str .. " " .. k2
    end
end

if min_qty == 1 then
    print("Least recorded value was = " ..key2.. " recorded "..min_val.." times")
else
    print("Least recorded values were = " ..min_str.. " each recorded "..min_val.." time")
end
if max_qty == 1 then
    print("Most recorded value was = " ..key1.. " recorded "..max_val.." times")
else
    print("Least recorded values were = " ..max_str.. " each recorded "..max_val.." time")
end
print("---------------------------")

Lua - 分析文本文件中的值

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