Print Using "##"

Here is a simple function to convert numbers using the format:


Function PrintUsing(formatString$, value)
result$ = ""
totalWidth = 0
decimalPlaces = 0
inDecimal = false
decimal_index = -1

' Parse the format string to determine total width and decimal places
for ch_index = 0 to Len(formatString$)-1
ch$ = Mid(formatString$, ch_index, 1)
if ch = "#" then
if inDecimal then
decimalPlaces = decimalPlaces + 1
end if
totalWidth = totalWidth + 1
elseif ch = "." then
inDecimal = true
decimal_index = ch_index
end if
next

int_val = Int(value)
ds$ = Insert(Replace(str(frac(value)) + StringFill("0", decimalPlaces), ".", ""), ".", decimalPlaces+1)
decimal_val$ = Str(Round(Val(ds$)))
output_str$ = Str(int_val) + "." + decimal_val

Print output_str$
End function

PrintUsing("##.#", 66.789)

You would need to modify it to handle the other formatting QBasic can do but most formatting is just the decimal places so it does cover most situations I have seen.