Re: "+ -" in an output line?
- To: mathgroup at smc.vnet.net
- Subject: [mg52298] Re: [mg52275] "+ -" in an output line?
- From: yehuda ben-shimol <benshimo at bgu.ac.il>
- Date: Sun, 21 Nov 2004 07:23:40 -0500 (EST)
- References: <200411200841.DAA08791@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Out[13] is not kept as a standard "Mathematical expression". It is kept
within a header of a SeriesData as you can see below. The - comes from
the Complex[0,-1] and the + comes (probably) from some sort of
displaying this object as a mathematical expression on the screen but
not evaluated..
Running the following commands
a = Series[-I q s - I p Sqrt[K12 - s2], {s, 0, 1}];
FullForm[a]
SeriesData[s, 0, List[Times[Complex[0, -1],
p, Power[Plus[K12, Times[-1, s2]], Rational[1,
2]]], Times[Complex[0, -1], q]], 0, 2, 1]
will show you that.
But if you run
b = Normal[a];
FullForm[b]
Plus[Times[Complex[0, -1], q, s], Times[Complex[0, -1], p,
Power[Plus[K12, Times[-1, s2]], Rational[1, 2]]]]
you can notice that this is an evaluated regular expression of Mathematica
Anyway, I think that this should not appear and hope it will be corrected
yehdua
AES/newspost wrote:
>The input
>
> In[13]:=
> Series[-I q s - I p Sqrt[K1^2 - s^2], {s, 0, 1}]
>
>gives
>
> Out[13]=
> -I Sqrt[K1^2] p + - I q s + O[s^2]
>
>whereas
>
> In[14]:=
> Series[-I q s - I p Sqrt[K1^2 - s^2], {s, 0, 1}] // Normal
>
>gives
>
> Out[14]=
> -I Sqrt[K1^2] p - I q s
>
>What's that "+ -" doing in Out[13] ? Is this normal?
>
>
>
- References:
- "+ -" in an output line?
- From: AES/newspost <siegman@stanford.edu>
- "+ -" in an output line?