How to plot an array in negative axes

I have initialized an array using the following code:

xdim=6;
ydim=12;
V_new=zeros(xdim+1,ydim+1);
V_new(5,4:10)=15;
V_new

Now, I want to plot this array from x=-3:9 and y=0:6.

However, I am not sure how to plot the array at the negative x-axis.

[Image Analyst]

What does it mean, exactly, to "plot" a matrix? Do you mean surf()? Or does each row or each column show up as a line plot in a graph? Please clarify. Also tell us if you have ever heard of the xlim() and ylim() functions to set the plot ranges of the graph.

[dpb]

Say what!? You have an array that is all zeros except for seven elements in the 5th row that are a constant.

What's to plot and what possible relation is there between the array and two totally unrelated variables

x =-3:9
y = 0:6

???

[Anum Ahmed]

Actually the complete code goes like this:

xdim=6; 
ydim=12; 
V=zeros(xdim+1,ydim+1); 
V_new=zeros(xdim+1,ydim+1); 
V_new(5,4:10)=15;
error=15; 
iter=0; 
while(error>0.0001) 
   iter=iter+1; 
     for i=2:1:xdim 
        for j=2:1:ydim
           if V_new(i,j) == 15 
              continue 
           end 
          V_new(i,j)=(V_new(i-1,j)+V_new(i+1,j)+V_new(i,j-1)+V_new(i,j+1))/4; 
        end 
     end 
 error=max(max(abs(V_new-V))); 
 V=V_new; 
end
figure('Name', 'Contours of Electric Potential');   
contour(flipud(V),15,'ShowText','on') 
grid on

It is used to determine the potential for a box. The plotted result are according to the array I initially defined. However, I want to plot the results from x=-3:9 and y=0:6.

Answer 1

[dpb]

Ah...ok, now I see...presuming the array is assumed to match box boundaries, just define X,Y to match the dimensions you want--

X=linspace(-3,9,size(V,2));
Y=linspace(0,5,size(V,1));
contour(X,Y,flipud(V),15,'ShowText','on')
...

[Anum Ahmed]

Greta, it works... Thanks a lot...!!!

[dpb]

No problem; I just "whiffed" on the question first go... :)