3D plot: draw xy grid line on the middle of the plot box

I have a 3D plot. The grid lines typically render at limiting planes of the plot box. I'd like them to render on a plane inside those limits. For example, I have a box that is +/-2 units in x, y, and z. I turn off the z grid. I'd like the xy grid to render in the xy plane at z=0. Is there a way to do this with out explicitly drawing lines manually?

[William Rose]

@Lloyd Bumm,

You can move the axes in a 2D plot, as shown below. If you could move the axes in a 3D plot, maybe the gridlines would move too. But XAxisLocation and YAxis location seem ineffecual in a 3D plot.

x=-2:.05:2; y=2*sin(x*pi);
figure
plot(x,y); grid on
ax=gca; ax.XAxisLocation='origin'; ax.YAxisLocation='origin';

Here's the 3D version. The axis locations do not move to the origin, despite the command to do so.

x=-2:0.2:2; y=-2:0.2:2;
[X,Y]=meshgrid(x,y);
Z=-2+4*exp(-(X.^2+Y.^2)/4);
surf(X,Y,Z); grid on; 
ax=gca; ax.XAxisLocation='origin'; ax.YAxisLocation='origin';

Maybe someone else knows the way to make it happen.

[Lloyd Bumm]

You can controll the axes crossing point like this:

fh.XRuler.FirstCrossoverValue = YAcross; % X crossover with Y axis

fh.XRuler.SecondCrossoverValue = ZAcross; % X crossover with Z axis

fh.YRuler.FirstCrossoverValue = XAcross; % Y crossover with X axis

fh.YRuler.SecondCrossoverValue = ZAcross; % Y crossover with Z axis

fh.ZRuler.FirstCrossoverValue = XAcross; % Z crossover with X axis

fh.ZRuler.SecondCrossoverValue = YAcross; % Z crossover with Y axis

Answer 1

[William Rose]

@Lloyd Bumm,

Try grid3() on the File Exchange., by @Hristo Zhivomirov.

x=-2:0.2:2; y=-2:0.2:2;
[X,Y]=meshgrid(x,y);
Z=-2+4*exp(-(X.^2+Y.^2)/4);
surf(X,Y,Z);
grid3(x,y,0)

●

You could edit the function to get black or gray grid points, if you prefer.

[Lloyd Bumm]

Thanks, I need to try grid3.

Answer 2

[Lloyd Bumm]

I ended up just using xline and yline. That worked well because I wanted the grid ot be at z=0. Otherwise I'd need to use the plot limits and an elevation to creat the grid lines.

function draw_grid
    grid_color = [0.15 0.15 0.15];
    grid_alpha = 0.15;
    x_ticks = [-20 -10, 0, 10, 20, 30];
    for ii = 1: length(x_ticks)
        xline(x_ticks(ii),'color',grid_color,'LineWidth',2,'alpha',grid_alpha);
    end
    y_ticks = [-10, 0, 10, 20, 30];
    for ii = 1: length(y_ticks)
        yline(y_ticks(ii),'color',grid_color,'LineWidth',2,'alpha',grid_alpha);
    end
end