How to stop running code once conditions are met?

Question

Micah 2023-4-8

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1943924-how-to-stop-running-code-once-conditions-are-met

编辑： James Tursa 2023-4-8

Hey guys, I'm trying to determine the average amount of people it would take to have two peopleh have the same birthday. Essentially I'm looking at the birthday paradox as an assignment for school. I haven't added the part where the function will run multiple times just yet. I'm still trying to figure out how to stop the program once two of the same number are rolled, store how many times that took, and then repeat for a thousand iterations. I know that this is probably not the best way to go about handling the code, but I'm having a hard time figuring out how else to go about it. I was thinking about using a while loop, but I don't know what the conditional statment would be.

function F = Birthday
% Birthday Paradox
%generates
%
% Outputs:
% Number of people before two people have the same birthday
%Created on:4/6/23
%Created by: M. Bruce
%Initialization
F = zeros(1,1000);
for n = 1:1000
    F(n) = randi(365);
    for k = 1:n-1
        if F(n) == F(n-k)
            break
        else
            return
        end
    end
end

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 2023-4-8

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1943924-how-to-stop-running-code-once-conditions-are-met#answer_1212134

在 MATLAB Online 中打开

  found_duplicate = false; 
  for k = 1:n-1
        if F(n) == F(n-k)
            found_duplicate = true;
            break
        end
  end
  if found_duplicate
      do the statistics stuff
  end

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。

Answer 2

James Tursa 2023-4-8

0
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1943924-how-to-stop-running-code-once-conditions-are-met#answer_1212139

编辑：James Tursa 2023-4-8

在 MATLAB Online 中打开

If your Birthday function is supposed to represent only one trial (a reasonable thing to do), then you should be returning n, not F. And when your inner for-loop finds a match, it needs to break out of both loops, not just the inner loop. E.g.,

% Some trials
for k=1:10
    Birthday
end
ans = 37
ans = 17
ans = 37
ans = 36
ans = 17
ans = 21
ans = 11
ans = 27
ans = 37
ans = 23
function n = Birthday % one trial of the birthday paradox
% Birthday Paradox
%generates
%
% Outputs:
% Number of people before two people have the same birthday
%Created on:4/6/23
%Created by: M. Bruce
%Initialization
F = zeros(1,365);
for n = 1:365
    F(n) = randi(365);
    for k = 1:n-1
        if F(n) == F(n-k) % could simply use F(k) here instead of F(n-k)
            return % done, so break out of both loops and return n
        end
    end
end
end