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 IEEE vs. Microsoft Binary Format; Rounding Issues (Complete) - Q35826
 
    Method 2
    --------
 
    This routine is much more complicated than the first method, though
    it handles a much larger range of values. The value being rounded
    is multiplied by 100# and this result must fit within the range of
    valid double precision numbers.
 
    ' To try this example in VBDOS.EXE:
    ' 1. From the File menu, choose New Project.
    ' 2. Copy the code example to the Code window.
    ' 3. Press F5 to run the program.
 
    FUNCTION round$ (number#) STATIC
    number# = INT((number# + .005) * 100#) / 100#
    hold$ = STR$(number#)
    hold$ = RTRIM$(LTRIM$(hold$))
 
    IF (MID$(hold$, 1, 1) = "-") THEN
      new$ = "-"
      hold$ = MID$(hold$, 2)
    ELSE
      new$ = ""
    END IF
 
    x = INSTR(hold$, "D")
    DecimalLocation = INSTR(hold$, ".")
 
    IF (x) THEN  ' Scientific notation.
      exponent = VAL(MID$(hold$, x + 1, LEN(hold$)))
      IF (exponent < 0) THEN
        new$ = new$ + "."
        new$ = new$ + STRING$(ABS(exponent) - 1, ASC("0"))
        round$ = new$ + MID$(hold$, 1, 1)
      ELSE
        new$ = new$ + MID$(hold$, 1, DecimalLocation - 1)
        num = LEN(hold$) - 6
        IF num < 0 THEN
          num = exponent
        ELSE
          num = exponent - num
       new$ = new$+MID$(hold$, DecimalLocation+1, x-DecimalLocation-1)
        END IF
        new$ = new$ + STRING$(num, ASC("0")) + ".00"
        round$ = new$
      END IF
 
    ELSE  ' Not scientific notation.
      x = INSTR(hold$, ".") 'find decimal point
      IF (x) THEN
        IF MID$(hold$, x + 3, 1) = "9" THEN
          xx = VAL(MID$(hold$, x + 2, 1)) + 1
          hold1$ = LEFT$(hold$, x)
          IF xx = 10 THEN
      hold1$ = hold1$+LTRIM$(STR$(VAL(MID$(hold$, x + 1, 1)) + 1))+"0"
            round$ = new$ + hold1$
          ELSE
            hold1$ = hold1$ + MID$(hold$, x + 1, 1) + LTRIM$(STR$(xx))
            round$ = new$ + hold1$
          END IF
        ELSE
          round$ = new$ + LEFT$(hold$, x + 2)
        END IF
      ELSE
        round$ = new$ + hold$
      END IF
    END IF
    END FUNCTION