Convert xy Coordinates to Matrix

42 次查看（过去 30 天）

John 2013-5-26

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/76990-convert-xy-coordinates-to-matrix

评论： Image Analyst 2021-3-24

I have an xy coordinates positions (100x2) and another z vector (100x1) with values corresponding to each xy coordinate. How can I make a matrix of the coordinates with the position of each coordinate having the corresponding z value? Thanks!

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

Andrei Bobrov 2013-5-27

2
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/76990-convert-xy-coordinates-to-matrix#answer_86743

编辑：Andrei Bobrov 2013-5-27

在 MATLAB Online 中打开

after John's comment in Image Analyst's answer:

out = accumarray([x(:),y(:)],z(:),[10 10]);

out = zeros(10);
out(sub2ind(size(out),x,y)) = z;

4 个评论
显示 2更早的评论隐藏 2更早的评论

John 2013-5-27

Now I get it, thanks for the clarification.

cecilia dip 2016-11-28

Hi, I have to do the same thing, and i've tried this, but my coordinates (x,y) are negative and non-integer numbers, as they are latitude,longitude.. how can i do this? I want a plot where for each(lat,long) i can have my Z value (in a color scale, as i will compare it with interpolation methos later). Thank you!

请先登录，再进行评论。

更多回答（2 个）

Image Analyst 2013-5-26

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/76990-convert-xy-coordinates-to-matrix#answer_86643

在 MATLAB Online 中打开

Try this:

% Setup / initialization.
% Start out matrix as zeros.
m = zeros(20,10);
% Generate 100 random coordinates.
xy = int32(randi(10, 100, 2));
% Get matrix values for those x,y locations
z = randi(255, 100, 1); % 100 values.
% Now, do what the poster, John, wants to do.
% Assign the z values to the (x,y) coordinates at the corresponding row.
% E.g. m at (x(1), y(1)) will have a value of z(1).
% m at (x(2), y(2)) will have a value of z(2).  And so on.
indexes = sub2ind([20, 10], xy(:,1), xy(:,2))
m(indexes) = z