RE: Plot[f[x], {x,a,b}] Not Reaching End Points

*To*: mathgroup at smc.vnet.net*Subject*: [mg29093] RE: [mg29028] Plot[f[x], {x,a,b}] Not Reaching End Points*From*: "Wolf, Hartmut" <Hartmut.Wolf at t-systems.de>*Date*: Tue, 29 May 2001 02:57:21 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

> -----Original Message----- > From: aes [mailto:siegman at stanford.edu] To: mathgroup at smc.vnet.net > Sent: Friday, May 25, 2001 7:48 AM > To: mathgroup at smc.vnet.net > Subject: [mg29093] [mg29028] Plot[f[x], {x,a,b}] Not Reaching End Points > > > When I execute > > n=0.1; Plot[ (1-x)^n, {x,0,1} ] > > the plot stops well short of dropping all the way to the > baseline on the > steeply falling edge as x approaches 1 --- even if I use > PlotRange->All > or expand to something unreasonable like PlotPoints->10000. > > I understand that a Plot routine can have difficulties dealing with > singularities or rapidly varying functions within the range to be > plotted -- but it seems surprising to me that it should totally pass > over or omit an explicitly stated, nonsingular end point. > Well, I don't think this to be a bug, but well intended behaviour, which I consider to be quite useful mostly (i.e. giving the least irritation for all use cases). Your example overstresses the plot point sampling algorithm. So if you do have a very steep function behaviour for an elsewhere flat function graph, you are free to increase the number of plot points *locally* ! For your case try: Plot[(1 - x)^n, {x, 1 - 10^#, 1}, DisplayFunction -> Identity] & /@ Range[0, -20, -7]; Show[%, DisplayFunction -> $DisplayFunction, PlotRange -> All] -- Hartmut