Attribute number to closed area

Hi,

I'm trying to calculate stable region automatically by Matlab. As shown in picture, Boundries are driven (as 2 vector of x,y) and split the plate into several closed areas.

Every closed area has a specific number and Somehow these numbers are related to each other.

I have to :

1. Define very closed area
2. Attribute an number (for example 2) for each Area

at last The area with least number is The stable region.

I have coordinates of intersections (Red Points), I was thinking about using these points and "inpolygon" command to find a point within The area and attribute the number to that point instead of whole surface. But Vertex Points are not connected Respectively (e.g 3th, 4th and 8th are making an area) and that does not work for me.

Could you please help me out of this ?

Answer 1

[Bruno Luong]

You might checkout POLYSHAPE, that can give you the regions

P = polyshape(rand(10,2));
R = regions(P);

close all
plot(R);
for k=1:length(R)
    [x,y]=R(k).centroid;
    text(x,y,num2str(k));
end

[Armin Mashhadi]

Thank you very very much,

It probebly solved my problem, exepct that holes!

It would not connect all verteces so some empty areas will be created !

Even "ishole" says no hole is in the plot :(

[Bruno Luong]

The white part is the complement of P: meaning the surounding rectangle substracted P. Checkout boolean operation of polyshape to get that complement.

Repeat the same process wuth the complement.

Box = polyshape([0 0;
                 1 0;
                 1 1;
                 0 1;
                 0 0]);
P = polyshape(rand(10,2));
Q = subtract(Box, P);
R1 = regions(P);
R2 = regions(Q);
R = [R1; R2];

close all
plot(R);
for k=1:length(R)
    [x,y]=R(k).centroid;
    text(x,y,num2str(k));
end

[Armin Mashhadi]

Thanks a lot, that worked for me ..