Re: strange bug?
- To: mathgroup at smc.vnet.net
- Subject: [mg79193] Re: strange bug?
- From: "David W.Cantrell" <DWCantrell at sigmaxi.net>
- Date: Fri, 20 Jul 2007 03:37:21 -0400 (EDT)
- References: <f7n4k9$24e$1@smc.vnet.net>
"Jeremy Price" <cfgauss at u.washington.edu> wrote: > I think I've found a bug in mathematica 5.2, > > In[418]:= > $Version > > Out[418]= > 5.2 for Microsoft Windows (June 20, 2005) > > When I run, eg, > > In[416]:= IntegerPart[10*5.1] > > Out[416]= 51 > > I get what I expect. But when I run the same thing in a loop, > > For[n = 1, n < 20, n = n + .1, Print[n, " ", IntegerPart[10*n]]] > > I get output like: > > >From In[415]:=4.9 48 > > >From In[415]:=5. 49 > > >From In[415]:=5.1 50 > > >From In[415]:=5.2 51 > > Any idea what's going on here or how to fix it? Just change your increment from .1 to the precise value 1/10: For[n = 1, n < 20, n = n + 1/10, Print[N[n], " ", IntegerPart[10*n]]] David