[Date Index] [Thread Index] [Author Index]

Re: evaluating functions and displaying results numerically

• To: mathgroup at smc.vnet.net
• Subject: [mg126162] Re: evaluating functions and displaying results numerically
• From: Murray Eisenberg <murray at math.umass.edu>
• Date: Sun, 22 Apr 2012 06:05:39 -0400 (EDT)
• Delivered-to: l-mathgroup@mail-archive0.wolfram.com
• References: <201204210433.AAA29272@smc.vnet.net>
• Reply-to: murray at math.umass.edu

Correct, the result of Sin[1] is _exactly_ Sin[1], whereas Sin[1.] will 
give you a decimal result that approximates the exact value.

This is one of the most basic ideas of Mathematica -- that it can deal 
with exact symbolic quantities, like Pi or E or Sqrt[2] or Sin[1].

Perhaps you need to read some of the introductory tutorials provided 
with Mathematica.

On 4/21/12 12:33 AM, 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
>

-- 
Murray Eisenberg                     murray at math.umass.edu
Mathematics & Statistics Dept.
Lederle Graduate Research Tower      phone 413 549-1020 (H)
University of Massachusetts                413 545-2859 (W)
710 North Pleasant Street            fax   413 545-1801
Amherst, MA 01003-9305

• References:
  • evaluating functions and displaying results numerically
    • From: Eduardo Fontana <prof.eduardofontana@gmail.com>