Slice of a 3D plot and projection of that function in a plane.

I'm trying to plot the mesh-plot of a Gaussian beam and slice through the centre. With it I'm tring to project the 3D plot on a plane together too. I'm using-

x = linspace(-2,2,100); y = linspace(0,2,100);
[X,Y] = meshgrid(x,y);
Rho2 = X.*X + Y.*Y;
Z = exp(-Rho2);

figure,
mesh(X,Y,Z,'FaceAlpha',1);  hold on  
contourf(X,Y,Z,70,'edgecolor','none'),colormap cool 

But now the 2D Gaussing is also cut at the centre. Is there any way I can get the sliced 3D Gaussin and full 2D Gaussian together.

I appreciate your help.

Answer 1

[Matt J]

[x,y,yhalf]=deal(linspace(-2,2,100));
yhalf(y<0)=nan;

Z = exp(-( x.^2 + y.^2'));

figure,
mesh(x,yhalf,Z,'FaceAlpha',1);  hold on  
contourf(x,y,Z,70,'edgecolor','none'),colormap cool 

[U B]

Cool. Thanks.

Answer 2

[Star Strider]

II’m not certain what result you want.

Try this —

x = linspace(-2,2,100); y = linspace(0,2,100);
[X,Y] = meshgrid(x,y);
Rho2 = X.*X + Y.*Y;
Z = exp(-Rho2);

x2 = linspace(-2,2,100);
y2 = linspace(-2,2,100);

[X2,Y2] = meshgrid(x2,y2);
Rho22 = X2.*X2 + Y2.*Y2;
Z2 = exp(-(X.^2 + Y2.^2));

figure,
mesh(X,Y,Z,'FaceAlpha',1);  hold on  
contourf(X2,Y2,Z2,70,'edgecolor','none'),colormap cool 

The approach here iis to define ‘y2’ over the full extent, and then recalculate ‘Z2’ using a slightly different function, and then reecalculate the contourf plot using them.

.

[U B]

Oh just by chnaging the axis we can get it. Thank you so much.

[Star Strider]

My pleasure!