Re: Not Plotting Vertical Assymptotes

*To*: mathgroup at smc.vnet.net*Subject*: [mg18616] Re: [mg18542] Not Plotting Vertical Assymptotes*From*: "Wolf, Hartmut" <hwolf at debis.com>*Date*: Tue, 13 Jul 1999 01:01:36 -0400*Organization*: debis Systemhaus*References*: <199907100618.CAA02940@smc.vnet.net.>*Sender*: owner-wri-mathgroup at wolfram.com

Hello Patrick Patrick McLean schrieb: > > Anyone have any idea how to stop Plot putting a (near) vertical line at > x=2 in the command: > > Plot[1/(1-x),{x,0,2}] > > ie. detect that the function 1/(1-x) has a singularity at x=2 and do > something about it. This is analagous to numerically integrating over a > (integrable) singularity, where the following remedy works: > > NIntegrate[1/Abs[Sqrt[x-1]]^2,{x,0,1,2}] > > But in this case it doesn't work. Decreasing MaxBend works a bit but the > line is still there. > Perhaps there is a better method, but a quick fix would be: In[3]:= g1=Plot[1/(1-x),{x,0,1},DisplayFunction->Identity] In[4]:= g2=Plot[1/(1-x),{x,1,2},DisplayFunction->Identity] In[5]:= Show[g1,g2,PlotRange->{{0,2},Automatic},DisplayFunction->$DisplayFunction] maybe that helps a little bit (Of course you could forge the idea to a real program) .... ....ok, e.g. like that: In[31]:= Unprotect[Plot] In[32]:= Plot[f_,{var_Symbol,min_,sing__,max_},opts___]:= Module[{ranges=Prepend[#,var]&/@Partition[{min,sing,max},2,1], g}, g=Map[Plot[f,#,opts,DisplayFunction->Identity]&,ranges]; Show[g,DisplayFunction->$DisplayFunction]] In[33]:= Protect[Plot] In[34]:= Plot[1/((1-x)(2-x)),{x,0,1,2,3},PlotRange->{All,{-50,50}}] ---your's hw

**References**:**Not Plotting Vertical Assymptotes***From:*p_mclean@postoffice.utas.edu.au (Patrick McLean)