Determining area considering nodes arranged in space in an almost circular shape

Hi. I have the attached nodes arranged in space. I would like to calculate the area having the nodes as boundaries.

I'm trying this way but it doesn't seem to work (the blue line does not follow the red nodes).

figure

x = plane_new(:,1);
y = plane_new(:,2);

k = boundary(x(:),y(:));
plot(x,y,'.-r')
line(x(k),y(k))

A = polyarea(x(k),y(k));

Answer 1

[Dyuman Joshi]

Directly use polyarea -

load('plane_new.mat')

x = plane_new(:,1);
y = plane_new(:,2);

plot(x,y,'.-r')

A = polyarea(x,y)

A = 42.3674