How to change NaN values of a matrix to 1 drawing a polygon
2 views (last 30 days)
Show older comments
how to use all the indixes inside the polygon h we draw with the following code to change NaN values of X matrix to 1.
load('quest.mat')
imagesc(f,ct,X)
h = drawpolygon('FaceAlpha',0);
xp=repelem(f,103,1);
yp=repmat(ct,256,1);
rpos=(f(2)-f(1))*floor(h.Position/ct(2)-ct(1))
in = inpolygon(xp,yp,rpos(:,1),rpos(:,2));
X(in)=1;
0 Comments
Answers (1)
Image Analyst
on 21 Nov 2021
Try it this way:
load('quest.mat')
subplot(2, 2, 1);
X(1) = 0;
imshow(X, []);
g = gcf;
g.WindowState = 'maximized';
uiwait(helpdlg('Draw a polygon. Double-click to finish it'))
h = drawpolygon('FaceAlpha',0);
xy = h.Position;
xp= xy(:, 1);
yp= xy(:, 2);
% rpos=(f(2)-f(1))*floor(h.Position/ct(2)-ct(1))
% in = inpolygon(xp,yp,rpos(:,1),rpos(:,2));
% X(in)=1;
[rows, columns] = size(X)
mask = poly2mask(xp, yp, rows, columns);
subplot(2, 2, 2);
imshow(mask)
X(mask) = 255;
subplot(2, 1, 2);
subplot(2, 2, 3);
imshow(X, []);
0 Comments
See Also
Categories
Find more on Elementary Polygons in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!