How can I find distances to the chosen point from all the other points ( Euclidean distance ) ?

1 次查看（过去 30 天）

Damian Wierzbicki 2017-6-26

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/346313-how-can-i-find-distances-to-the-chosen-point-from-all-the-other-points-euclidean-distance

评论： Damian Wierzbicki 2017-6-28

Hi all, Let's assume that I have a huge matrix and say that I pick a point from that matrix. Is there a way of calculating euclidean distance from all the other points of that matrix and store them separately in the matrix of the same dimension where the number in each entry of a matrix is a number that represents the Euclidean distance to the pre-chosen point ?? Thank you

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。

采纳的回答

Image Analyst 2017-6-27

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/346313-how-can-i-find-distances-to-the-chosen-point-from-all-the-other-points-euclidean-distance#answer_272052

在 MATLAB Online 中打开

Assuming you mean in spatial space (which ignores the actual matrix values and just looks at their location), and not in intensity or value space (which compares differences in intensity or value of the matrix to some other intensity or value), then you can do:

% Setup
rows = 4;  % For example
columns = 5;
% x and y can be column and row indexes, respectively, but they don't have to be.
x = 1;  % For example
y = 1;
% Now compute the distances from every element to (x, y).
[XGrid, YGrid] = meshgrid(1:columns, 1:rows)
distances = sqrt((x - XGrid) .^ 2 + (y - YGrid) .^ 2)

7 个评论
显示 5更早的评论隐藏 5更早的评论

Image Analyst 2017-6-28

It looks like that's what Jan's code does. You can have his X be any number of rows and columns. And Point would be X(someRowIndex, someColumnIndex).

Damian Wierzbicki 2017-6-28

在 MATLAB Online 中打开

    B = zeros (rows , columns ); 
for c = 1:columns 
   for r = 1:rows 
    if ref_matrix ( r , c ) == 0 
     B = 0; 
       elseif ref_matrix ( r , c ) ~= 0 
        B = ( r , c ) = distances ( r , c ); 
  end 
 end 
end
% found a mistake, this a working version.