Your X and Y coordinates are reversed when you construct mySpace. The
correct code is: 
     mySpace = new ObjectGrid2D(20,45);

This is why, when you add to the grid in the X dimension (incrementing x),
it has wrapped around at y == 20.


On 1/26/18, 7:04 AM, "MASON Multiagent Simulation Toolkit on behalf of
Stewart Aitken" <[log in to unmask] on behalf of
[log in to unmask]> wrote:

>I have a query about ObjectGrid2D(x, y), here is a snippet of code.
> public void buildModel() {
>        mySpace = new ObjectGrid2D(45,20);
>        agents = new Bag();
>        for (int i=0; i<initNumberOfAgents; i++) {
>            agents.add(new Agent6(this));
>        }
>    }
>I am creating different size grids in rectangular form with the same
>amount of cells as the square grid.
>The code is a rectangle for 900 cells and the square has x =  30 and y =
>The square cells can all be accessed. I had assumed that a rectangle with
>x = 20 and y = 45 would work as well.
>However it does not. If I place the 20 in the x position then the agents
>as they fill the grid only fill to y == 19 which is 20 and then jumps to
>y == 0.
>After a while I rearanged the x, y to y, x and once again the agents can
>access all cells.
>I have looked in manual 19 and not found that ObjectGrid2D(x, y) is
>correct. it will be helpful if it can be confirmed either way.
>all the best,