3D voxel data without input

Hi guys, i have this code to create a 3D voxel grid and a cube within. But I wanna change my code such that i wont need to enter the input in the command windows but rather execute the function and the grid will be displayed.

That is the code:

    function voxel(i,d,c,alpha);
switch(nargin),
case 0
    disp('Too few arguements for voxel');
    return;
case 1
    l=1;    %default length of side of voxel is 1
    c='b';  %default color of voxel is blue
case 2,
    c='b';
case 3,
    alpha=1;
case 4,
    %do nothing
otherwise
    disp('Too many arguements for voxel');
end;
x=[i(1)+[0 0 0 0 d(1) d(1) d(1) d(1)]; ...
        i(2)+[0 0 d(2) d(2) 0 0 d(2) d(2)]; ...
        i(3)+[0 d(3) 0 d(3) 0 d(3) 0 d(3)]]';
for n=1:3,
    if n==3,
        x=sortrows(x,[n,1]);
    else
        x=sortrows(x,[n n+1]);
    end;
    temp=x(3,:);
    x(3,:)=x(4,:);
    x(4,:)=temp;
    h=patch(x(1:4,1),x(1:4,2),x(1:4,3),c);
    set(h,'FaceAlpha',alpha);
    temp=x(7,:);
    x(7,:)=x(8,:);
    x(8,:)=temp;
    h=patch(x(5:8,1),x(5:8,2),x(5:8,3),c);
    set(h,'FaceAlpha',alpha);
    axis equal
    axis([0,10,0,10,0,10])
    xlabel('X-Achse')
    ylabel('Y-Achse')
    zlabel('Z-Achse')
    grid on
end;

At this moment i write e.g. voxel([5 5 5],[1 1 1],'b',0.7); in the command windws for the input. How can i change my code ????

THX