Formatting a number into #,###,###?

[Jasoco]

I know it's simple, but I don't know the syntax.

How would I format a number like 93522341 into 93,522,341? Adding commas?

[kikito]

I can't help you much, but I can give you a start.

Lua provides a string.format function, which will convert a number to string, like so:

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local number = 1234567890
local snumber = string.format("%d", number) -- "1234567890"

Now the problem has been transformed in "insert one comma between every 3 characters of a string". This is probably doable with regular expressions. But I can't help you with that part. Lua's reliance on regular expressions for string manipulation is one of the things I don't like about it.

Good luck!

EDIT: OK I got this:

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snumber:reverse():gsub( "(%d%d%d)" , "%1," ):reverse():gsub("^,","") -- "1,234,567,890"

If you want the complete thing:

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function commaformat(number)
   return string.format("%d", number):reverse():gsub( "(%d%d%d)" , "%1," ):reverse():gsub("^,","")
end

Simple, huh?

[Jasoco]

Sad. In QBASIC there was a simple PRINT "#,###,###", var that could be called that would format the number for you. But I've never seen it anywhere else. So I've always had to just dissect the number as a string into three character segments and glue them back together. I was hoping Lua had a method to work around that. Guess not. Oh well. I'll have to do it the same way I always do.

[pekka]

EDIT: Posting removed because this thread is only for incorrect solutions

[thelinx]

Here's my (one-line) solution:

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local formattedNumber = (tostring(myNumber):reverse():gsub("%d%d%d", "%1,"):reverse():gsub("^,", ""))

[kikito]

Oh, yes, tostring. I forgot about it.

[thelinx]

Hey, I didn't see you edited your post? Blasphemy! I was the original master of everything pure and shiny!

[pekka]

EDIT: Posting removed

[Jasoco]

Thanks! They work great! I knew there was a fairly simple one-line solution.

[pekka]

EDIT: Posting removed