Scientific Notation
#6
(11-10-2022, 09:55 AM)Pete Wrote: Actually, I think you need a semi colon, not a comma there...

Code: (Select All)
PRINT USING "####.##########"; a

Anyway, there are a lot of these floating point bombs to contend with.Here's two simple addition ones that differ with variable types.

Code: (Select All)
DIM a AS DOUBLE
FOR i = 1 TO 10
    a = a + .01
    PRINT a ' Bombs at iteration 7.
NEXT

DIM b as SINGLE
FOR i = 1 TO 10
    b = b + .01
    PRINT b ' Bombs at iteration 10.
NEXT

PRINT USING and FIX() are a couple of workarounds but for better reliability across a large number spectrum you need to consider using something like my string math routine, I believe Mark and Steve have ones of their own, too, or Jack's excellent numeric dec-float routine. Of course you need to call these as libraries and add them with an $INCLUDE statement or just get comfortable with a sub addition that consists of several hundreds of lines.

Pete

Yeah but expensive in LOC and there always seems to be something else you need to fix!
Here we need a rounder and that usually needs to convert number back from string.
Code: (Select All)
_Title "N2S$ Test Steve's converter for number display" ' b+ 2022-11-10

Dim a As Double
For i = 1 To 10
    a = a + .01
    Print a; Tab(40); N2S$(Str$(a)) ' Bombs at iteration 7.
Next

Dim b As Single
For i = 1 To 10
    b = b + .01
    Print b; Tab(40); N2S$(Str$(b)) ' Bombs at iteration 10.
Next

' call N2S$(Str$(YourNumberOfAnyType))
Function N2S$ (EXP$) 'remove scientific Notation to String (~40 LOC)
    'SMcNeill Jan 7, 2020 ref: https://www.qb64.org/forum/index.php?topic=1555.msg112989#msg112989
    'Last Function in code marked Best Answer (removed debug comments and blank lines added these 2 lines.)
    ReDim t$, sign$, l$, r$, r&&
    ReDim dp As Long, dm As Long, ep As Long, em As Long, check1 As Long, l As Long, i As Long
    t$ = LTrim$(RTrim$(EXP$))
    If Left$(t$, 1) = "-" Or Left$(t$, 1) = "N" Then sign$ = "-": t$ = Mid$(t$, 2)
    dp = InStr(t$, "D+"): dm = InStr(t$, "D-")
    ep = InStr(t$, "E+"): em = InStr(t$, "E-")
    check1 = Sgn(dp) + Sgn(dm) + Sgn(ep) + Sgn(em)
    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!
    Select Case l 'l now tells us where the SN starts at.
        Case Is < dp: l = dp
        Case Is < dm: l = dm
        Case Is < ep: l = ep
        Case Is < em: l = em
    End Select
    l$ = Left$(t$, l - 1) 'The left of the SN
    r$ = Mid$(t$, l + 1): r&& = Val(r$) 'The right of the SN, turned into a workable long
    If InStr(l$, ".") Then 'Location of the decimal, if any
        If r&& > 0 Then
            r&& = r&& - Len(l$) + 2
        Else
            r&& = r&& + 1
        End If
        l$ = Left$(l$, 1) + Mid$(l$, 3)
    End If
    Select Case r&&
        Case 0 'what the heck? We solved it already?
            'l$ = l$
        Case Is < 0
            For i = 1 To -r&&
                l$ = "0" + l$
            Next
            l$ = "." + l$
        Case Else
            For i = 1 To r&&
                l$ = l$ + "0"
            Next
            l$ = l$
    End Select
    N2S$ = sign$ + l$
End Function

Another case solved by string math!
b = b + ...
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Messages In This Thread
Scientific Notation - by james2464 - 11-10-2022, 04:27 AM
RE: Scientific Notation - by BSpinoza - 11-10-2022, 04:56 AM
RE: Scientific Notation - by james2464 - 11-10-2022, 05:31 AM
RE: Scientific Notation - by Pete - 11-10-2022, 09:55 AM
RE: Scientific Notation - by bplus - 11-10-2022, 04:02 PM
RE: Scientific Notation - by mnrvovrfc - 11-10-2022, 04:52 PM
RE: Scientific Notation - by james2464 - 11-10-2022, 03:54 PM
RE: Scientific Notation - by bplus - 11-10-2022, 04:36 PM
RE: Scientific Notation - by Pete - 11-10-2022, 04:41 PM
RE: Scientific Notation - by bplus - 11-10-2022, 05:18 PM
RE: Scientific Notation - by Pete - 11-10-2022, 05:37 PM
RE: Scientific Notation - by SMcNeill - 11-10-2022, 08:03 PM
RE: Scientific Notation - by bplus - 11-10-2022, 08:43 PM
RE: Scientific Notation - by Pete - 11-10-2022, 09:40 PM



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