Re: Round[1.5] != Round[3/2] = 2 ???
- To: mathgroup at smc.vnet.net
- Subject: [mg3501] Re: Round[1.5] != Round[3/2] = 2 ???
- From: rhall2 at umbc.edu (hall robert)
- Date: Mon, 18 Mar 1996 00:58:06 -0500
- Organization: University of Maryland, Baltimore County
- Sender: owner-wri-mathgroup at wolfram.com
In article <4ibblj$fep at ralph.vnet.net>,
Peter Foldiak <Peter.Foldiak at st-andrews.ac.uk> wrote:
>On my Unix (SG) version of Mathematica I get this strange
>behaviour:
[snip]
>The book says "Round rounds numbers of the form x.5 towards 0."
>Well, sometimes, it appears. Am I doing something wrong or is this a
>bug?
For rational numbers, Round[] rounds to the even integer.
In[5]:=
Round[ 3/2 ]
Out[5]=
2
In[6]:=
Round[ 5/2 ]
Out[6]=
2
But in the alternative universe of decimal fractions,
Round[] rounds toward 0, as stated in
"Mathematica: A System for Doing Ontology by Computer."
In[2]:=
Round[ 3/2 // N ]
Out[2]=
1
In[7]:=
Round[ 5/2 // N ]
Out[7]=
2
Thus, reality depends on which universe you occupy.
--
Bob Hall | "Know thyself? Absurd direction!
rhall2 at gl.umbc.edu | Bubbles bear no introspection." -Khushhal Khan Khatak
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