Re: Point is not a Graphics primitive?
- To: mathgroup at smc.vnet.net
- Subject: [mg85189] Re: Point is not a Graphics primitive?
- From: Szabolcs <szhorvat at gmail.com>
- Date: Thu, 31 Jan 2008 05:50:50 -0500 (EST)
- References: <fnrnkn$oim$1@smc.vnet.net>
On Jan 31, 6:51 am, "Kevin J. McCann" <Kevin.McCann at umbc.edu> wrote:
> The following gives me an error. I would have thought that Point was a
> Graphics primitive, but vers 6 says no. Any help would be appreciated.
> BTW a 2D equivalent works fine.
> Plot3D[Sin[x y], {x, -2, 2}, {y, -2, 2},
> Epilog -> {Red, AbsolutePointSize[7], Point[{0, 0, 0}]}]
>
Hi,
This is tricky: those things that you put in the Prolog/Epilog are
treated as 2D, not 3D. To combine 3D graphics, just use Show[].
Try this:
Plot3D[Sin[x y], {x, -2, 2}, {y, -2, 2},
Epilog -> {Red, AbsolutePointSize[7], Point[{.5, .5}]}]
The point will be drawn in the middle of the image.
And this is what you were trying to achieve:
Show[Plot3D[Sin[x y], {x, -2, 2}, {y, -2, 2}],
Graphics3D[{Red, AbsolutePointSize[7], Point[{0, 0, 0}]}]]
I hope this helps,
Szabolcs