Re: bug in IntegerPart ?

*To*: mathgroup at smc.vnet.net*Subject*: [mg47961] Re: bug in IntegerPart ?*From*: ancow65 at yahoo.com (AC)*Date*: Sun, 2 May 2004 04:51:03 -0400 (EDT)*References*: <c6vhrn$gcq$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Daniel Lichtblau <danl at wolfram.com> wrote in message news:<c6vhrn$gcq$1 at smc.vnet.net>... > [.deleted.] > > > We already agreed that 'decimal' != 'approximate' (at least in > > mathematics). > We have agreed to no such thing. By universal convention (okay, > universal - 1), 1.65 is an approximate number. > Ok, I will agree (for a moment :-)). What is that something that you are approximating with 0.35? Is that NumberForm[0.35, 100] => 0.35 or NumberForm[1.65-1.3,15] => 0.35 0.35 or NumberForm[1.65 - 1.3, 16] => 0.3499999999999999 0.3499999999999999 NumberForm[1.65 - 1.3, 100] => 0.3499999999999999 0.3499999999999999 Oops, it looks like I came accross a bug. Let's try again your favorite RealDigits. RealDigits[0.35] => {{3, 5, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, 0} 3.500000000000000 RealDigits[1.65-1.3] => {{3, 4, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9}, 0} 3.499999999999999 1.65-1.3 // FullForm => 0.34999999999999987` Do you claim that 'approximate' are decimals that don't have finite binary representation or all decimals? Just asking. :-) So maybe this is that 'perfect' number. 2^^0.0101100110011001100110011001100110011001100110011001100110011001100110011\ 001100110011 => 0.3500000000000000000000000 I tried to check more digits, but I filled out the whole line. When I added the continuation mark \ and more digits in the next line, an error occured: Mathematica has detected a possible internal error. If possible, report the error to support at wolfram.com, quoting "Assertion 'ibuf == ((box)->nchars)' failed at matheditio.c:2093", and describe in as much detail as possible what you were doing when the error occurred. Mr. Lichtblau, it look like a job for you. I think I will stop my quest for a perfect number here. AC > [.deleted.] > > Daniel Lichtblau > Wolfram Research