Re: Plot3D question
- To: mathgroup at smc.vnet.net
- Subject: [mg70668] Re: [mg70622] Plot3D question
- From: "Chris Chiasson" <chris at chiasson.name>
- Date: Sun, 22 Oct 2006 01:20:37 -0400 (EDT)
- References: <200610210914.FAA29129@smc.vnet.net>
I am not sure that cases command is working as you intend because it
contains Set[x,0] instead of Equal[x,0]
On 10/21/06, dimitris <dimmechan at yahoo.com> wrote:
> Hello again.
>
> I would like to know why the Plot3D function does not complain about
> the following command
> (note there is a singularity at y=0)
>
> Plot3D[Sin[x]/y, {x, -10, 10}, {y, -10, 10}]
>
> whereas it does complain (a lot!) about the following
>
> Plot3D[Sin[x]/y, {x, -10, 10}, {y, -10, 10}]
>
> I believe it has to do with the non-adaptive algorithm used by Plot3D,
> but even the command
>
> Plot3D[Sin[x]/y, {x, -10, 10}, {y, -10, 10},PlotPoints->100]
>
> does not change the behavior.
>
> Note that I don't have any problem why the Plot function does not
> complain about the
> following command
>
> Plot[Sin[x]/x, {x, 0, 10}];
>
> since I understand that the adaptive algorithm actually does not sample
> points at x=0
>
> Short[Cases[%, {x_?NumberQ, y_?NumberQ} /; x = 0 && y > 0.9, 8], 2]
>
> I really appreciate any comments/guidance/insight.
>
> Thanks
> Dimitris
>
>
--
http://chris.chiasson.name/
- References:
- Plot3D question
- From: "dimitris" <dimmechan@yahoo.com>
- Plot3D question