Why am I loosing a row and a column in MATLAB slice plot?

I am trying to plot a 3D volume in MATLAB. I am using the slice command.

    a(:,:,1)=[1,2; 3,4];
    a(:,:,2)=[5,6; 9,8];
    figure;
    slice (a,0,0,1);
    hold on
    slice (a,0,0,2);

The figure I get has just one square (pixel). I am expecting 4 squares. How do I plot this? What am I doing wrong?

Answer 1

[Walter Roberson]

Under "Tips" for slice() you will see

The color drawn at each point is determined by interpolation into the volume V.

This is the same issue that hits pcolor: an NxM matrix has (N-1)x(M-1) interior locations.