Interpolation of grid data inside of an ellipse

I have a plot of an ellipse with gridded data inside. the grid data is not uniformly distributed so there are squares with different size. I would like to interpolate these squares with the ellipse. As you can see in the second figure, there is a gap between the ellipse and last produced squares. How can I properly mergethe last square to the edge of the ellipse? I have 2 vectors which are xS (360*1) and yS(360x1) that has coordinates of edge of ellipse. I have another two matrix has the corners of each square such as CoordsX (2172x4) and CoordsY (2172x4).

[KSSV]

You can increase the resolution and use inpolygon to get the points lying inside the ellipse.

Or generate scattered data inside the ellipse.

[Prabhan Purwar]

Hey,

I do agree with KSSV, increasing resolution along with inpolygon should work. Could you attach your implementation code so that we can suggest something better?

Thanks