Re: Re: Outputting to file with fixed decimal digits
- To: mathgroup at smc.vnet.net
- Subject: [mg75321] Re: [mg75285] Re: Outputting to file with fixed decimal digits
- From: Daniel Lichtblau <danl at wolfram.com>
- Date: Wed, 25 Apr 2007 05:34:34 -0400 (EDT)
- References: <f0ekbt$pnn$1@smc.vnet.net> <200704240719.DAA27260@smc.vnet.net>
do.not at reply.nonet wrote:
> Larry
> [...]
>
> I have suggested using the "Floor" function - it's to avoid the
> "Round" function which has the most bizarre definition in Mathematica
> - it doesn't give the same answer every time.
> (Look in "Further Examples" in the Help on "Round")
> It's one reason that makes me think Mathematica is not really
> "Engineering Grade" software and suspicious that there may be more
> weird things that I just haven't come across yet.
>
> Robert
Here is what I find in Help > Round > Further Examples from version 5.2.
---------------
To avoid statistical bias Round alternates between going up and down
halfway between integers.
In[1]:=
Round[Range[10]+.5]
Out[1]=
{2,2,4,4,6,6,8,8,10,10}
The function NumericRound rounds all parts of the numeric coefficients
of a polynomial.
In[2]:=
NumericRound[x_]:=MapAll[If[NumericQ[#],Round[#],#]&,x]
In[3]:=
\!\(NumericRound[\@\[Pi] + \((\[ExponentialE] + a)\)\ x + \((4.3 -
8.6 \[ImaginaryI]\ )\) x\^3]\)
Out[3]=
\!\(1 + \((3 + a)\)\ x + \((4 - 9\ \[ImaginaryI])\)\ x\^3\)
In[4]:=
Clear[NumericRound]
---------------
I do not see examples that show changes to their results upon repetition.
Daniel Lichtblau
Wolfram Research
- References:
- Re: Outputting to file with fixed decimal digits
- From: do.not@reply.nonet
- Re: Outputting to file with fixed decimal digits