Formatting Decimal Currency

[AtomicSlaughter]

So this SUB came about because I'm currently writing an EPOS system, and could not for the life of me get the math to work properly due to floaty math.

The inability for QB64 to track numbers to the decimal place with accuracy and getting sick of having my program write 1.9 to screen as £1.90 i wrote this piece of code to convert the integers into a string to print to screen.

it is a bit lacking as I first have to convert the integer to string, but this simplifies the process some what.

It is very useful to me, hopefully someone else will find it useful in their program.

Code: QB64: [Select]

1. SUB Currency (a$)
2.     l = LEN(a$)
3.     penny$ = RIGHT$(a$, 2)
4.     IF LEN(penny$) = 1 THEN
5.         pound$ = "0"
6.         penny$ = "0" + penny$:
7.         conv$ = pound$ + "." + penny$
8.         a$ = conv$
9.     ELSE
10.         pound$ = LEFT$(a$, (l - 2))
11.         conv$ = pound$ + "." + penny$
12.         a$ = conv$
13.     END IF
14.     IF LEN(conv$) = 3 THEN a$ = "0" + conv$
15. END SUB

[SpriggsySpriggs]

I have WinAPI code for this as well. When I get back to a PC I will give it to you.

[bplus]

and could not for the life of me get the math to work properly due to floaty math.

When I was testing Steve's N2S$ (Number to String converter), I was pretty happy. I think it might be used in IDE? because his Math Evaluator is and this is where that came from, if I recall correctly.

Code: QB64: [Select]

1. Option _Explicit
2. _Title "N2S$ testing for a scientific notation remover" 'b+ 2020-09-04
3. ' source of bug tracked down 2020-09-08
4. ' looks pretty good except for one little bug fixed now
5.  
6. 'It was because i was not dim'd as an integer!!!
7. Dim i As Integer '<<<<<<<<<<<<<<<<<<<< Oh man!!!!  this was the problem!!! Discovered 2020-09-08
8. Dim n##
9. If 0 Then ' < 0 to skip section, 1 to run section
10.     Dim n As Integer '<<<<<<<<<<< comment out to test single
11.     n = 1 ' has an odd bug jump -7 to -8 moves right 1 extra 0   fixed!!
12.     For i = 0 To 20
13.         Print i,
14.         Locate CsrLin, 5: Print N2S$(Str$(n * 10 ^ -i));
15.         Locate CsrLin, 54: Print N2S$(Str$(n * 10 ^ i))
16.     Next
17. Else
18.     Beep
19.     n## = 1 ' but this OK too
20.     'n## = 27.0123456789 'OK
21.     'n## = (1 / 3) 'OK
22.     For i = 0 To 20
23.         Print i;
24.         Locate CsrLin, 5: Print N2S$(Str$(n## * 10 ^ -i));
25.         Locate CsrLin, 54: Print N2S$(Str$(n## * 10 ^ i))
26.     Next
27.     Beep
28. End If
29.  
30. Function N2S$ (EXP$) 'remove scientific Notation to String (~40 LOC)
31.     'SMcNeill Jan 7, 2020 ref: https://www.qb64.org/forum/index.php?topic=1555.msg112989#msg112989
32.     'Last Function in code marked Best Answer (removed debug comments and blank lines added these 2 lines.)
33.     ReDim t$, sign$, l$, r$, r&&
34.     ReDim As Long dp, dm, ep, em, check1, l, i
35.     t$ = LTrim$(RTrim$(EXP$))
36.     If Left$(t$, 1) = "-" Or Left$(t$, 1) = "N" Then sign$ = "-": t$ = Mid$(t$, 2)
37.     dp = InStr(t$, "D+"): dm = InStr(t$, "D-")
38.     ep = InStr(t$, "E+"): em = InStr(t$, "E-")
39.     check1 = Sgn(dp) + Sgn(dm) + Sgn(ep) + Sgn(em)
40.     If check1 < 1 Or check1 > 1 Then N2S = _Trim$(EXP$): Exit Function 'If no scientic notation is found, or if we find more than 1 type, it's not SN!
41.     Select Case l 'l now tells us where the SN starts at.
42.         Case Is < dp: l = dp
43.         Case Is < dm: l = dm
44.         Case Is < ep: l = ep
45.         Case Is < em: l = em
46.     End Select
47.     l$ = Left$(t$, l - 1) 'The left of the SN
48.     r$ = Mid$(t$, l + 1): r&& = Val(r$) 'The right of the SN, turned into a workable long
49.     If InStr(l$, ".") Then 'Location of the decimal, if any
50.         If r&& > 0 Then
51.             r&& = r&& - Len(l$) + 2
52.         Else
53.             r&& = r&& + 1
54.         End If
55.         l$ = Left$(l$, 1) + Mid$(l$, 3)
56.     End If
57.     Select Case r&&
58.         Case 0 'what the heck? We solved it already?
59.             'l$ = l$
60.         Case Is < 0
61.             For i = 1 To -r&&
62.                 l$ = "0" + l$
63.             Next
64.             l$ = "." + l$
65.         Case Else
66.             For i = 1 To r&&
67.                 l$ = l$ + "0"
68.             Next
69.             l$ = l$
70.     End Select
71.     N2S$ = sign$ + l$
72. End Function
73.  

After converting, just find decimal place and add (00's) | remove excess digits.