How do I find the area of a shape?

My goal for this code is to find the area inside of a polygon, or any shape really. I know that one way of doing it would be to input the coordinate points of the shape's corners, but I'm not sure how to get area from that. I think there should be a way to create an integration field within the original shape and by integrating a cross sectional area like a triangle, inside the original shape, and summing multiple integrations together, I should be able to find the total area, I'm just not sure how to translate these thoughts into code. Could anyone give me a hand?

Answer 1

[Walter Roberson]

https://www.mathworks.com/help/matlab/ref/polyarea.html

and see https://www.mathworks.com/matlabcentral/answers/122705-how-to-calculate-the-perimeter-and-area-of-a-polygon

[Jacquelyn Hermosillo]

Thank you!