Creating a binary Matrix from X and Y Coordinates

I have a vector of X coordinates and a vector of Y coordinates that together form a closed shape. This shape is plotted in a larger window of other shapes and pictures. I want to create a matrix that can be overalyed on the aforementioned larger window and referenced whose only values are ones and zeros. I want the ones to be the shape created by the X and Y vectors and everything inside it, and the zeros to be everything else. Any ideas for how to do this efficiently? The goal is to have a matrix that can be referenced against the original window that only contains the information on the space occupied by the one specific shape.

Answer 1

[Matt J]

As long as X and Y are matrix indices, you can do

matrix=accumarray([X(:),Y(:)],1,targetSize);

where targetSize is the desired size of the resulting matrix.