Re: Dumb question
- To: mathgroup at smc.vnet.net
- Subject: [mg27780] Re: Dumb question
- From: Erk Jensen <Erk.Jensen at cern.ch>
- Date: Fri, 16 Mar 2001 04:37:35 -0500 (EST)
- Organization: CERN http://www.cern.ch
- References: <98neji$8g@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Gustavo Seabra wrote: > > 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 > ----------------------------------------------------------------- 1) I see you're new since you're using the wrong type of brackets for Mathematica. Probably you mean (Sin[(a-x) t]/(a-x))^2 There is no problem to plot this, since in Plot[f,{variable,min,max}] you can specify which is the variable for the plot, which are the parameters - in your case you may want to try p=(Sin[(a-x) t]/(a-x))^2 Plot[p/.{a->Pi/2,t->1},{x,0,Pi}] 2) You will not see any discontinuity since there is none. There is only a hole, but the lim from both sides will be the same, so you can fill the hole, e.g. defining (attn., this is not exactly your expression!) si[x_ /; x == 0] := 1 si[x_ /; x != 0] := Sin[x]/x It's exactly like the function x/x which has a hole at x=0 ... - so what! Ciao -erk-