清空筛选条件
清空筛选条件

How to get a random 50x14 matrix from 300x14 matrix

1 次查看（过去 30 天）
Amirali AGHAMIRI
Amirali AGHAMIRI 2022-3-27
评论： Amirali AGHAMIRI 2022-3-28
Hello,
Could you please tell me how to get a random 50x14 matrix from 300x14 matrix?
  4 个评论
显示 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
Image Analyst 2022-3-27
Perhaps this, if you want all 50 rows to be adjacent to each other and not randomly chosen.
% Define matrix.
m = randi(9, 300, 14)
% Get starting and ending rows
startingRow = randi(size(m, 1)-49, 1, 1)
endingRow = startingRow + 49
% Extract a band of 50 contiguous rows
m50 = m(startingRow : endingRow, :);
  3 个评论
显示 1更早的评论
Image Analyst
Image Analyst 2022-3-28
Ran in:
So just delete the first line where I created an m. I just did that because you keep forgetting to attach your actual matrix in a .mat file with the paperclip icon.
% Get starting and ending rows
startingRow = randi(300-49, 1, 1)
startingRow = 207
endingRow = startingRow + 49
endingRow = 256
As you can see above when I ran it, it would take all rows between 207 and 256 of your original matrix and extract them to a new matrix called m50. Why do you think that will not work for your matrix?

请先登录，再进行评论。

更多回答（1 个）

Torsten
Torsten 2022-3-27
编辑：Torsten 2022-3-27
A = rand(300,14);
p = randperm(300,50);
B = A(p,:)

类别

在 Help Center 和 File Exchange 中查找有关 Creating and Concatenating Matrices 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by