Re: Mathematica bugs?
- To: mathgroup at smc.vnet.net
- Subject: [mg67316] Re: Mathematica bugs?
- From: "David W.Cantrell" <DWCantrell at sigmaxi.org>
- Date: Sun, 18 Jun 2006 05:13:02 -0400 (EDT)
- References: <e70f29$rf4$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
"Yaroslav Bulatov" <yaroslavvb at gmail.com> wrote: > When I run the following line > x = Pi/4; For[i = 0, i < 56, i += 1, x = 2*Abs[x - 1/2]]; N[x] > I get 3. > > But x should always stay between 0 and 1, why do I get 3? > > Also > x = Pi/4; For[i = 0, i < 50, i += 1, x = 2*Abs[x - 1/2]]; N[Log[x]] > gives me Indeterminate > > How can I get an indeterminate here? Just ask for more precision from N: In[107]:= x = Pi/4; For[i = 0, i < 56, i += 1, x = 2*Abs[x - 1/2]]; N[x,20] Out[107]= 0.79387245267980382900 In[108]:= x = Pi/4; For[i = 0, i < 50, i += 1, x = 2*Abs[x - 1/2]]; N[Log[x],20] Out[108]= -3.3676443458316025909 David Cantrell