Repeat for loop until condition is met.

Question

Matlab User 2017-3-2

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/327772-repeat-for-loop-until-condition-is-met

评论： John BG 2017-3-2

I am drawing random numbers within an interval. I know that in the end I want 20 of them, but only those that meet a condition, for example, generation between 1:10 and then only keeping those less than 5. I need to loop over this until 20 are found... I'm not allowed to just generate between 1:5 which would solve this unfortunately! I have something like this..

Number_req=20;
n = zeros(20,1); 
for k=1:Number_req 
 x=[];
  x=10*rand(1,1);
 if x(k)<= 10 
    n(k) = x
 else
     if x(k)>10
          break
     end
 end
end

1 个评论
显示 -1更早的评论隐藏 -1更早的评论

John BG 2017-3-2

在 MATLAB Online 中打开

who or what is not allowing you to just do the following

randi([1 4],1,20)

generating random numbers within [1:10] but not getting any within [5:10] is, if not considering time, exactly the same as generating random numbers within [1:4]

are you familiar with the Bayes theorem?

John BG

<mailto:jgb2012@sky.com jgb2012@sky.com>

请先登录，再进行评论。

请先登录，再回答此问题。

Answer 1

James Tursa 2017-3-2

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/327772-repeat-for-loop-until-condition-is-met#answer_257004

编辑：James Tursa 2017-3-2

在 MATLAB Online 中打开

It would be easier to use a while loop. E.g., modifying your code and replacing your for-loop with a while-loop:

% Insert your beginning stuff here
k = 1;
while k <= Number_req
    r = _______;  % insert your random number generation stuff here
    if( ____________ )  % Insert your test code for r here
        x(k) = r;
        k = k + 1;
    end
end