how to join these random points in a desired rectangle shape automatically by programming..

Question

VANDANA GUPTA 2019-5-1

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/459577-how-to-join-these-random-points-in-a-desired-rectangle-shape-automatically-by-programming

评论： VANDANA GUPTA 2019-5-8

i am able to join these points in rectangle by manually arrange in order..but i want to arrange automatically in programming by image processing techniques... i also checked chaincode method in image processing..this is beneficial for 8-connected points but my points are not adjacent neighbors.. I have two vectors f1 in x-axis and f2 in y-axis..

f1 = [25.0 25.0 25.0 25.0 25.0 26.8 27.4 29.8 30.2 32.2 33.6 33.9 35 35 35 35]
f2 = [-3.5 -4.9 0.9 -5.3 -0.4 1.9 -5.3 1.6 -5.3 1.7 -5.3 1.8 -5.5 -4.9 -3.1 0]

points are like:

(25.0, -3.5)

(25.0, -4.9)

(25.0, 0.9)

(25.0, -5.3)

(25.0, -0.4)

(26.8, 1.9)

(27.4, -5.3)

(29.8, 1.6)

(30.2, -5.3)

(32.2, 1.7)

(33.6, -5.3)

(33.9, 1.8)

(35, -5.5)

(35, -4.9)

(35, -3.1)

(35, 0)

0 个评论
显示 -2更早的评论隐藏 -2更早的评论

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

Walter Roberson 2019-5-1

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/459577-how-to-join-these-random-points-in-a-desired-rectangle-shape-automatically-by-programming#answer_373105

在 MATLAB Online 中打开

k = boundary(f1(:), f2(:), 0.5);
plot(f1(k), f2(k));

The 0.5 parameter can be adjusted. The largest that works is about 0.777

4 个评论
显示 2更早的评论隐藏 2更早的评论

Walter Roberson 2019-5-1

Yes. You can use discretize the coordinates and write to locations at the appropriate offsets, using a double array (or at least not a logical array.) Then you can regionprops() that array; regionprops will see that the array is not logical and will treat the values as label numbers, and since the labels are all the same, will treat everything as belonging to one object (that happens to have a lot of holes in it.) The 'boundingbox' property will then tell you where the lower left corner is of a box that includes all of the points, together with the height and the width.

This is an "image processing" approach to the problem.

It is also wasteful. If all you care about is the bounding box, just take min() and max() of the X and Y coordinates.

VANDANA GUPTA 2019-5-8

thank you very much sir...

请先登录，再进行评论。

Answer 2

VANDANA GUPTA 2019-5-8

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/459577-how-to-join-these-random-points-in-a-desired-rectangle-shape-automatically-by-programming#answer_374079

c.png
p.png

sir, i have an one more query. i made a 2-d figure 'c.png' in matlab by using r and theta and with the help of boundary function as u helped..now i want to make a figure 'p.png' from previous figure..i made it manually but i want to make it automatically by programming ..may you help me?