Re: Dumb question
- To: mathgroup at smc.vnet.net
- Subject: [mg27788] Re: [mg27772] Dumb question
- From: Tomas Garza <tgarza01 at prodigy.net.mx>
- Date: Sat, 17 Mar 2001 05:41:12 -0500 (EST)
- References: <200103140907.EAA00012@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
I'm afraid there is no such discontinuity at x = a. To see this, take
In[1]:=
p = (Sin[a - x]*t/(a - x))^2;
(there is a convention in Mathematica that all user-defined symbols or
functions should start with a lower-case letter, so as not to clash with
built-in functions, which always begin with upper-case; also, the use of
square brackets [] is restricted to functions and commands). Then you have
In[2]:=
Limit[p, x -> a, Direction -> 1]
Out[2]=
t^2
In[3]:=
Limit[p, x -> a, Direction -> -1]
Out[3]=
t^2
(check The Book or the on-line help browser to know more about the option
Direction in Limit) and so, by definition the function p is continuous at x
= a, for any choice of t. Then there should be no problem to obtain its
graph, for any particular values of t and a. E.g.,
In[4]:=
Plot[p /. {t -> 1, a -> Pi/2}, {x, 0, Pi}];
where the rules "->", together with "ReplaceAll" (abbreviated as "/.") are a
way of substituting particular values in the function p.
Tomas Garza
Mexico City
----- Original Message -----
From: "Gustavo Seabra" <gseabra at swbell.net>
To: mathgroup at smc.vnet.net
Subject: [mg27788] [mg27772] Dumb question
> Hello. I know this may be a dumb question, and I apologize for doing that.
> But I am new to Mathematica, and I'm having a little trouble with this. I
> want to plot the equation:
>
> P=[sin(a-x)*t/(a-x)]^2
>
> with fixed t (say, 1) and fixed a (say, Pi/2), with x varying from 0 to
Pi.
> I know there is a discontinuity at x=a. Is there a way to plot this? I
mean,
> P(x) versus x?
>
> Thanks,
> --
> -----------------------------------------------------------------
> Gustavo Seabra - Graduate Student
> Chemistry Department
> Kansas State University
> -----------------------------------------------------------------
>
>
- References:
- Dumb question
- From: Gustavo Seabra <gseabra@swbell.net>
- Dumb question