MathGroup Archive 2003

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: How to evaulate a function and graph it

  • To: mathgroup at smc.vnet.net
  • Subject: [mg43252] Re: [mg43206] How to evaulate a function and graph it
  • From: Dr Bob <drbob at bigfoot.com>
  • Date: Sat, 23 Aug 2003 08:08:26 -0400 (EDT)
  • References: <200308210224.WAA11224@smc.vnet.net>
  • Reply-to: drbob at bigfoot.com
  • Sender: owner-wri-mathgroup at wolfram.com

There's an uncountable infinity of points in that range, so you had better 
NOT need all of them!

Plot3D plots the points...

f[x_, y_] = x^4 + 3 x^2 + 5 y^2 + x + y;
plot = Plot3D[f[x, y], {x, -4, -3}, {y, -3, 4.3}];

The f values are saved as a 25 by 25 matrix in plot[[1]].

plot[[1]] == Table[N@f[x, y], {y, -3, 4.3, (4.3 + 3)/24}, {x, -4, -3, 
1/24}]

True

Bobby

On Wed, 20 Aug 2003 22:24:51 -0400 (EDT), Rebeca Choy <rchoy at ula.ve> wrote:

> Hi everyone,
>
> How can I evaluate a function of 2 variables, say:
>
> f(x,y) = x^4 + 3 x^2 + 5 y^2 + x + y
>
> in an interval of [-3.0,4.0] and[-3.0,4.3] for x and y?
>
> I need all the points between these two ranges to plot it
>
>
> Thanks
>
> Rebeca
>
>



-- 
majort at cox-internet.com
Bobby R. Treat


  • Prev by Date: How to evaluate a function and graph it--part 2
  • Next by Date: Iteration Interupt
  • Previous by thread: How to evaulate a function and graph it
  • Next by thread: Re: How to evaulate a function and graph it