3D PLOT please help

x=0:0.1:1000;

y=70:0.1:320;

z=4*pi*((0.032./(2.*pi.*8.31.*y)).^(3./2)).*
(x.^2).*exp((-0.032.*x.^2)./(2*8.31.*y));

plot3(x,y,z)

xlabel('Molecules Speed(m/s)'); ylabel('Temperature(K)'); zlabel('Probability');

this is the problem: Make a 3d plot of P(v)as a function of v and T for 0<v<1000 and 70<T<320

Molecules of gas in a container are moving at different speeds. Maxwell speed distribution law gives a probability P(v)

P(v)=4pi(M/(2piRT))^(3/2) * v^2 *e^((-Mv^2)/(2RT))

M=0.032

R= 8.31

this is the error I get

??? Error using ==> times
Matrix dimensions must agree.

Thanks for the feedback and help

Answer 1

[the cyclist]

To plot over a range of (x,y), you need the complete grid of coordinates. You can use the command meshgrid() to do this:

[xx,yy] = meshgrid(x,y);

Calculate z from xx and yy instead of x and y.

You probably want to decrease the granularity of your grid, otherwise you have way too many points to plot. It looked pretty good when I did

x=0:10:1000;
y=70:1:320;

[francis]

thanks I get it now