Re: Undesired horizontal line in Plot / Bug?
- To: mathgroup at smc.vnet.net
- Subject: [mg118158] Re: Undesired horizontal line in Plot / Bug?
- From: David Annetts <david.annetts at iinet.net.au>
- Date: Thu, 14 Apr 2011 07:08:54 -0400 (EDT)
Hi H,
Under Win-7 64bit and and ATI graphics card using Mathematica 8.0.1, I can't
reproduce what you describe, either with Frame or without.
D.
On 14/04/2011 16:48, H Hogreve wrote:
> A phenomenon that occasionally also occurs in other plots
> can be exemplified by setting
>
> fD[n_, cZ_] := 137^2/Sqrt[1 + cZ^2/(137*n + Sqrt[137^2 - cZ^2])^2];
>
> and plotting, e.g.,
>
> Plot[{fD[1, z], fD[5, z]}, {z, 1, 137}, Frame -> True,
> PlotRange -> Automatic]
>
> There is a horizonal line visible (parallel to the abscissa)
> that should not be there!! In fact, other plots like, e.g.,
>
> Plot[{fD[1, z], fD[2, z]}, {z, 1, 137}, Frame -> True,
> PlotRange -> Automatic]
>
> look fine, without this annoying additional line. Unfortunately,
> I could not find a way to remove or suppress this unwanted
> horizontal line in the first plot. Moreover, I observed this
> effect in all versions of Mathematica I have access to at the
> moment, i.e., four, six, and seven, and it makes me wonder
> whether this is a yet unresolved bug.
>
> Thus I would be very grateful for any hints on the questions
>
> - whether this horizontal line also occurs in the
> current Mathematica 8.0 ?
> - is there any remedy to prevent the line from being
> plotted or to remove it from the plot?
>
> Many thanks in advance for your kind help, H. Hogreve
>
> P.S.: If plotted without Frame, then this line does not
> occur, but apparently at its position the new abscissa
> is placed
>