Re: FractionalPart
- To: mathgroup at smc.vnet.net
- Subject: [mg31249] Re: FractionalPart
- From: "delouis" <ng_only at hotmail.com>
- Date: Tue, 23 Oct 2001 04:53:27 -0400 (EDT)
- References: <9qrco4$c02$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
I think the 1's that you are seeing are numbers who's fractional part are actually X.99999999 - and rounded to 1. In[45]:= SetPrecision[x[[7]],30] Out[45]= 6.99999999999999911182158029987 I am new myself, and am having a hard time figuring out how to see what the "Real" number is. I just do not like using N to return 10 digits, and always getting 6! I feel I just can not trust the answers that Mathematica 4.1 returns. In[47]:= N[Pi,10] Out[47]= 3.14159 Pi looks like a 6 digit number exactly. Note that an exact number like 1/2 gives accurate results. x = Exp[(1/2)*Log[A]] etc... Dana -- "Juan" <erfa11 at hotmail.com> wrote in message news:9qrco4$c02$1 at smc.vnet.net... > Hello. > I am new in Mathematica(also in english), and I have this question: > I would like to know the behavior of the function FractionalPart. > See here: > > In[1]:= a=Range[9]^2 > Out[1]= {1,4,9,16,25,36,49,64,81} > > In[2]:= x=Exp[.5 Log[a]] > Out[2]= {1,2.,3.,4.,5.,6.,7.,8.,9.} > > In[3]:= FractionalPart[x] > Out[3]= {0,0.,4.444089x10^-16,0.,0.,1.,0.,0.,1.,1.77639x10^-15} > > But it shoud be 0., all of them,no? > > Thanks. Juan > > > _________________________________________________________________ > Descargue GRATUITAMENTE MSN Explorer en http://explorer.msn.es/intl.asp > >