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Getting a random key from a dictionary table?

Asked by

BlackeyeI 19

5 years ago

Edited 5 years ago

I'm attempting to solve one of my previous queries and in order to have a breakthrough all I need to know is if it's possible to search through an entire table and store a random key within a variable while ignoring it's number values.

For example using this table I would like to randomly output one of the dictionary names such as Apples or Cabbages (quotations if possible) but NOT its number values.

Is this possible with tables or should I use a seperate modified table or array?

01ExampleTable = {
02["Apples"] = 0,
03["Berries"] = 32,
04["Cabbages"] = 5,
05["Daikons"] = 89,
06["Eggs"] = 9
07}
08 
09RandomKeySelector =
10 
11print("The random food item is",RandomKeySelector)

2 answers

Answered by

yHasteeD 1819

5 years ago

Edited 5 years ago

For get a Random key from dictionary table you need to create a array table with index of all elements of your dictionary table, For example:

01local dictionary = {
02    ["Eggs"] = 10,
03    ["Apples"] = 50
04}
05 
06local function GenerateRandom()
07    --> You need to create a fake array table.
08    local Array = {}
09 
10    for index in pairs(dictionary) do
11        table.insert(Array, index) --> Insert the index to array table
12    end
13 
14    --> After that only get the random number from array table.
15    local RandomNumber = math.random(1, #Array) --> Will get a random number of array
16 
17    return Array[RandomNumber], dictionary[Array[RandomNumber]] --> Return the name and value after that
18end
19 
20local Name, Value = GenerateRandom()
21 
22print(Name, Value)
 View all 22 lines...

Basically, i created a fake array table, added the index of the dictionary table, after that i generated the random value.

Fixed script:

01local ExampleTable = {
02    ["Apples"] = 0,
03    ["Berries"] = 32,
04    ["Cabbages"] = 5,
05    ["Daikons"] = 89,
06    ["Eggs"] = 9
07}
08 
09local function GenerateRandomIndex()
10    local Array = {}
11 
12    for index in pairs(ExampleTable) do
13        table.insert(Array, index)
14    end
15 
16    local RandomNumber = math.random(1, #Array)
17 
18    return Array[RandomNumber], ExampleTable[Array[RandomNumber]]
19end
20 
21local ObjName, ObjValue = GenerateRandomIndex()
22 
23print("The random food item is", ObjName, "The value is", ObjValue)
 View all 23 lines...

Hope it helped!

Too much work. Too bloated. Could have all been done in a single function call. User#24403 69 — 5y

Edited. yHasteeD 1819 — 5y

Answered by

namespace25 594

5 years ago

You want to use math.random(). Set the first argument to 1 and the next to #ExampleTable. The hashtag means it will get the length. If there were 5 items in the table, it would be 1, 5. But from my understanding of tables like this in the past, I had to put another table inside of the table because you can't get the name if the key has brackets around it.

01ExampleTable = {
02{Name="Apples",Number=0},
03{Name="Barries",Number=32},
04{Name="Cabbages",Number=5},
05{Name="Diakons",Number=89},
06{Name="Eggs",Number=9}
07}
08print(#ExampleTable)
09local numberPosition = math.random(1, #ExampleTable)
10RandomKeySelector = ExampleTable[numberPosition].Name
11 
12print("The random food item is ",RandomKeySelector)

A dictionary table will always return 0 when you try to get the length. That's why I removed it. namespace25 594 — 5y

Getting a random key from a dictionary table?

2 answers

Hope it helped!

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