Add comma separators to large numbers

It was hard to read a column of large numbers, so here's a function to add the commas. It is implemented in liveCode.

// make big integers readable by adding commas 

function addCommas z delim

  -- 4567 -> 4,567

  -- TTD make for for floats

  -- include option for european or other delimiter "."

  if delim is empty then put "," into delim

  put the number of chars of z into N

  put trunc((N - .01) / 3) into numCommas

  if numCommas > 0 then

    repeat with j = 1 to numCommas

      put delim before char (N - (j*3) + 1) of word 1 of z

    end repeat

  end if

  return z    -- z has been modified to contain commas

end addCommas

Use:

put addCommas(11456789)

Returns:

11,456,789

Long example:

on mouseUp

  put "" into fld "out1"

  repeat with i = 1 to 20

    put fibonacciNumber(i+31) into n  -- make big numbers

    put addCommas(n) into line i of fld out1

  end repeat

end mouseUp

// Returns the number at 1-based index pIndex >= 2 in the Fibonacci sequence

function fibonacciNumber pIndex

  local tFirst = 1, tSecond = 1

  local tCounter, tSum

  repeat with tCounter = 3 to pIndex

     put tFirst + tSecond into tSum

     put tSecond into tFirst

     put tSum into tSecond

  end repeat

  return tSecond

end fibonacciNumber

// make big integers readable by adding commas 

function addCommas z delim

  -- 4567 -> 4,567

  -- TTD make for for floats

  -- include option for european or other delimiter "."

  if delim is empty then put "," into delim

  put the number of chars of z into N

  put trunc((N - .01) / 3) into numCommas

  if numCommas > 0 then

    repeat with j = 1 to numCommas

      put delim before char (N - (j*3) + 1) of word 1 of z

    end repeat

  end if

  return z    -- z has been modified to contain commas

end addCommas

(find in livecode related ds/fibonacci_random_commas.livecode)