RE: Re: RE-GROUPING OF EXPRESS
- To: mathgroup@smc.vnet.net
- Subject: [mg11742] RE: [mg11661] Re: RE-GROUPING OF EXPRESS
- From: Ersek_Ted%PAX1A@mr.nawcad.navy.mil
- Date: Thu, 26 Mar 1998 03:09:09 -0500
Alternatively you can use StandardForm as the default format, and
evaluate the line below.
If you always want to use this form, you can put it in your (init.m)
file.
StandardForm does have the advantage that expressions like ArcTan[x]
are written in an unambiguous form, and can be used as input without
generating messages.
In[1]:=
MakeBoxes[(n_Real|n_Integer|n_Rational)*a_.+b_/;
(Head[b]=!=Plus)&&(n<0),form_]:=
RowBox[{MakeBoxes[b,form],"-", MakeBoxes@@{-n*a,form}}];
In[2]:=
b-a
Out[2]=
b-a
I know cryptic code like this makes Jerry Blimbbaum's blood boil. He
had that remark about a cryptic post I had earlier, and I am sure
others feel that way. Well with Mathematica you can get this via a
method that is more intuitive (use Traditional Form). On the other
hand Mathematica also lets you control things at a very low level.
Granted the code is cryptic, but it gives you much more flexibility.
Also some of us (myself included) like learning the more advanced
parts of the system as a hobby.
Ted Ersek
----------
|
|> My question concerns regrouping of variables, specifically terms |>
like (a-b) become transformed into -b + a (even though in the original
|> they are entered as a - b) which is a form I dont like nor does one
|> usually write equations that way. Is there anything one can do |>
about this
|
|If StandardForm is your Default Output FormatType (under the Cell menu)
|you get the behavior you describe:
|
| In[1]:= b-a
| Out[1]= -a+b
|
|However, you can convert the output to TraditionalForm manually, e.g.,
|
| In[2]:= b-a//TraditionalForm
| Out[2]= b-a
|
|or change your default to be TraditionalForm (which I personally
|prefer).
|
|> or why does Mathematica do it in the first place? |
|Mathematica often needs to do an internal re-ordering of expressions.
|TraditionalForm attempts to display the output in a form that
|corresponds to "standard" mathematical conventions. |
|Cheers,
|Paul Abbott