Generate 10 numbers from matrix
显示 更早的评论
Say I have a matrix, v1, how would I be able to randomly generate 10 numbers within the existing matrix?
2 个评论
Do you mean that you have, for example, a 5x5 matrix such as
M = magic(5)
and you want to select 10 numbers from that matrix at random?
Can you select the same number twice, or all 10 should be from a different position?
How do you want the output? A vector of 10 numbers?
For you future reference, please understand that if you had spent more writing out a more complete, thoughtful question, we would not need to clarify what you need.
Ashante Isabella Bon
2021-9-27
采纳的回答
Image Analyst
2021-9-23
To generate the numbers from random locations, without repeating any of the locations you need to use randperm(), not randi() like other answer(s). Using randi() will potentially allow the same location to be used multiple times. So use randperm() or randi() depending on what you want.
% Generate sample matrix -- a 7 row-by-9 column matrix.
m = randi(100, 7, 9)
% Get 10 random linear indexes with no location being a repeat:
randomIndexes = randperm(numel(m), 10)
% Extract data at those random locations:
extractedNumbers = m(randomIndexes)
更多回答（1 个）
Based on what you've stated the following could be what you want to obtain:
v1 = randi(10, 5, 5) %#ok % Is existing matrix
IDX = randi([1, 10], 1, 10); % Randomly select indexes from the existing matrix
R = v1(IDX) % Randomly selected 10 numbers from v1
类别
在 帮助中心 和 File Exchange 中查找有关 Random Number Generation 的更多信息
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!
Translated by 
