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Re: evaluating functions and displaying results numerically

• To: mathgroup at smc.vnet.net
• Subject: [mg126165] Re: evaluating functions and displaying results numerically
• From: "Nasser M. Abbasi" <nma at 12000.org>
• Date: Sun, 22 Apr 2012 06:06:41 -0400 (EDT)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com
• References: <jmtdec$sjd$1@smc.vnet.net>
• Reply-to: nma at 12000.org

On 4/20/2012 11:35 PM, Eduardo Fontana wrote:
> Once in a while a face a problem with Mathematica in which I cannot
> get a straightforward numerical output.
> I have a function defined in mathematica, I try to evaluate the
> function with numerical arguments and mathematica returns a replica of
> my function with the same arguments. It must be something I set
> without noticing. I cannot get numerical results at all.
> In another instance, I have a summation of about 1000 terms defined as
> a function of 3 arguments. When I use numerical arguments, instead of
> Mathematica calculating a numerical result it generates a symbolic
> output with all 1000 terms. Even if a try something very simple such
> as
> In[1]: Sin[1]
> the output is
> Out[1]: Sin[1]
> Could anyone give me a clue on this?
> regards
>

thats becuase it defaults to keeping things in
symbolic form.

If you want numeric result, then you need to tell it. Either use

In[2]:= Sin[1.]
Out[2]= 0.841471

or use N on the result

In[3]:= N[Sin[1],$MachinePrecision]
Out[3]= 0.8414709848078965

--Nasser