RE: Plot[f[x], {x,a,b}] Not Reaching End Points
- To: mathgroup at smc.vnet.net
- Subject: [mg29050] RE: [mg29028] Plot[f[x], {x,a,b}] Not Reaching End Points
- From: "David Park" <djmp at earthlink.net>
- Date: Sat, 26 May 2001 21:53:41 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
I think it is a minor bug in the Mathematica plotting algorithm that it does
not automatically include valid endpoints in the plot.
I tried the following, but it did not work either.
f[n_][x_] := (1 - x)^n
ParametricPlot[{x, f[0.1][x]}, {x, 0, 1},
PlotRange -> {0, 1}, PlotPoints -> 100];
However, the following trick does work, by putting the endpoint beyond x =
1. It doesn't even generate an error message!
Plot[ f[0.1][x](1 - UnitStep[x - 1]), {x, 0, 1.1}];
David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/
> From: aes [mailto:siegman at stanford.edu]
To: mathgroup at smc.vnet.net
>
> 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.
>