Hello Adele,
load('LavaField_example.mat')
thr=10; % Threshold to filter small lava regions
%% Max length of the whole lava field
r=regionprops('table',BWcumL,'Area','MaxFeretProperties');
r=r(r.Area>thr,:); % Retain only the large lava regions
r.MaxFeretDiameter % Max length of the main lava field
% Max distance the lava has flown from the center of the crater
B = bwboundaries(BWcumL);
Bpoints=B{1,1};
[xi,yi]=ind2sub([134,134],9046) % Position of the crater
D=pdist2(Bpoints,[xi,yi]); % Distance from the crater to the boundary
[MAX_FLOWN_DIST,n]=max(D);
% Plot
imshow(BWcumL)
hold on
A=r.MaxFeretCoordinates{1}; % Coordinates of the start-end point
plot(A(:,1),A(:,2),'-r')
plot(xi,yi,'o')
plot([Bpoints(n,2) xi],[Bpoints(n,1) yi])
l=legend({'MAX lava field length', 'Crater','Max lava field length from the crater'});
Hope this helps!
