Re: Question from Blind User
- To: mathgroup at christensen.cybernetics.net
- Subject: [mg1186] Re: Question from Blind User
- From: IANC (Ian Collier)
- Date: Mon, 22 May 1995 01:22:44 -0400
- Organization: Wolfram Research, Inc.
In article <3pjl8a$7h0 at news0.cybernetics.net>, mentat at telerama.lm.com
(Godshatter) wrote:
> Just installed the DOS version of Mathematica - the very last copy
> available, so they told me - and have run up against a problem in the way
> it displays answers. If you take the derivative of x^3, it gives the
> answer as:
>
> 2
> 3 x
>
> If I use a voice synthesyser to read the answer, it will come out as
> 2 3x. Using a braille display isn't much better, since I have to
> remember to look on more than one line for the answer.
>
> Is there any way to get the program to display answers in a more
> Fortran-like method?
>
> 3x^2
>
> I don't know how useful the program will be for me, if I have to look at
> multiple lines for the results. It is feasible to read equations spaced
> out on paper, but except for some very early arithmetic books, braille
> math books write equations and expressions one symbol after another.
> Besides, refreshable braille devices can display only one line at a time,
> and reading answers that way would involve a lot of extra keystrokes over
> the course of just a few problems.
>
> I would be grateful for any help. I would think that a program as
> powerful as Mathematica would allow for this kind of adjustment. Since
> the manual is rather large, I have not read it all yet. If the answer is
> in the documentation, just point me to it and I'll do the rest.
>
> Thanks in advance.
>
> Evan Reese
> mentat at telerama.lm.com
>
> "People are born with legs, not roots."
> R. Buckminster Fuller
You can do what you need using $Post, a global variable, which
is applied to every output expression if it is set.
Here is an example of a calculation carried out before and
after setting $Post to InputForm.
In[13]:=
Integrate[ 1/(x^4 + 1),x]
Out[13]=
-Sqrt[2] + 2 x Sqrt[2] + 2 x
ArcTan[--------------] ArcTan[-------------]
Sqrt[2] Sqrt[2]
---------------------- + --------------------- -
2 Sqrt[2] 2 Sqrt[2]
2 2
Log[1 - Sqrt[2] x + x ] Log[1 + Sqrt[2] x + x ]
----------------------- + -----------------------
4 Sqrt[2] 4 Sqrt[2]
In[14]:=
?$Post
$Post is a global variable whose value, if set, is applied
to every output expression.
In[15]:=
$Post = InputForm
Out[15]//InputForm=
InputForm
In[16]:=
Integrate[ 1/(x^4 + 1),x]
Out[16]//InputForm=
ArcTan[(-2^(1/2) + 2*x)/2^(1/2)]/(2*2^(1/2)) +
ArcTan[(2^(1/2) + 2*x)/2^(1/2)]/(2*2^(1/2)) -
Log[1 - 2^(1/2)*x + x^2]/(4*2^(1/2)) +
Log[1 + 2^(1/2)*x + x^2]/(4*2^(1/2))
You could apply any other formating that you wished using
$Post.
I hope this helps.
--Ian
-----------------------------------------------------------
Ian Collier
Technical Sales Support
Wolfram Research, Inc.
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tel:(217)-398-0700 fax:(217)-398-0747 ianc at wri.com
Wolfram Research Home Page: http://www.wri.com/
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