Well, I have a new function, this once's my favorite because it's not so ugly. It won't work for values smaller than 1.0e-004 so I cheat after that and just return Abs(value#). I couldn't fix the inaccuracies in these very small values, but none of the other versions could do this anyway. If you get any errors let me know what range they're in.
Open in online IDE;FloatFraction Graphics 640, 480, 0, 2 CheckSomeValues = 0 If CheckSomeValues For loop = 1 To 5 Select loop Case 1 : value# = -0.000000000000000000000000000000000000000000001 Case 2 : value# = -100000000000000000000000000000000000000.0 Case 3 : value# = -1.00126 Case 4 : value# = -0.00000000126 Case 5 : value# = -370001.6 End Select fraction# = FloatFraction(value#) Print "value# = " + value# + ", fraction# = " + fraction# Next WaitKey() End EndIf SeedRnd MilliSecs() For pow = -15 To 15 For loop = 0 To 10000 value# = Rnd(-9 * (10 ^ pow), 9 * (10 ^ pow)) valuestr$ = Float2Str(value#, 1) fraction# = FloatFraction(value#) fractionstr$ = Float2Str(fraction#, 0) If valuestr$ <> fractionstr$ Print "value# = " + value# + ", fraction# = " + fraction# Print " valuestr$ = " + valuestr$ + ", fractionstr$ = " + fractionstr$ errors = errors + 1 EndIf Next Print errors + " errors" + " when pow = " + pow errors = 0 Next Print "done" WaitKey() End Function FloatFraction#(Value#) ;Returns the fractional part of a float as a float ;The whole part and sign are removed Local Number#, Result#, Loop, StartExp Local EndExp, Pow#, Fraction#, Round# Number# = Abs(Value#) ;Remove the sign Result# = 0.1 For Loop = 1 To 38 ;Get whole places If Result# * 10 => Number# Then Exit Result# = Result# * 10 StartExp = StartExp + 1 Next If StartExp = 0 ;Value less than 1 Result# = Number# For Loop = 1 To 45 ;Get fractional places Result# = Result# * 10 If Int(Floor(Result#)) > 0 Then Exit StartExp = StartExp - 1 Next EndIf EndExp = StartExp - 6 Pow# = 1 For Loop = EndExp To -1 ;Get exponent Pow# = Pow# * 10 ;Instead of 10 ^ EndExp Next Fraction# = (Number# * Pow#) - (Floor(Number#) * Pow#) Round# = (Number# * Pow#) - (Floor(Number# * Pow#)) If Int(Round# * 10) = 5 ;Value after last meaningful place If Round# >= 0.5 Fraction# = Fraction# + 0.1 ;Round up Else Fraction# = Fraction# - 0.1 ;Round down EndIf EndIf Result# = Int(Fraction#) / Pow# If Result# >= 1.0 Then Result# = 0.0 ;Special case rounding error If StartExp > 37 Then Result# = 0.0 ;Special case for Infinity If StartExp < -4 Then Result# = Number# ;Cheat if value very small Return Result# End Function Function Float2Str$(Value#, RemoveWhole = 0) ;Converts a float into a string ;RemoveWhole -> Remove whole number flag, 0 = No, 1 = Yes ;Removes the exponent form Local Number$, Position, Result$, Exponent, Loop, Char$ Number$ = Str(Abs(Value#)) Result$ = Number$ If RemoveWhole Position = Instr(Number$, ".", 1) If Position Result$ = "0." + Right(Number$, Len(Number$) - Position) EndIf EndIf Position = Instr(Number$, "e-", 1) If Position Result$ = "0." Exponent = Right(Number$, Len(Number$) - Position - 1) For Loop = 1 To Exponent - 1 Result$ = Result$ + "0" Next For Loop = 1 To Len(Number$) Char$ = Mid(Number$, Loop, 1) If Char$ = "e" Then Exit If Char$ <> "." Then Result$ = Result$ + Char$ Next EndIf Position = Instr(Number$, "e+", 1) If Position Result$ = "" Exponent = Right(Number$, Len(Number$) - Position - 1) For Loop = 1 To Len(Number$) Char$ = Mid(Number$, Loop, 1) If Char$ = "e" Then Exit If Char$ <> "." Then Result$ = Result$ + Char$ Next For Loop = 1 To Exponent - 1 Result$ = Result$ + "0" Next Result$ = Result$ + ".0" If RemoveWhole Then Result$ = "0.0" EndIf Return Result$ End Function