Could anyone help me how to solve the following issue.

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I am using the command line
randi([1,5], 1, 10)
to generate numbers with respect to single row versus 10 columns.
when i run the command sometimes it generates all 5 numbers with respect to single row versus 10 columns in the following manner
3 1 2 1 1 4 4 5 2 5
sometimes it doesnt and i am getting the result as follows:
4 1 5 5 5 1 1 2 2 4(number 3 is missing)
But for me i want to have all 5 number every time when the command executes.Could anyone please help me on this.
  2 Comments
Rik
Rik on 28 May 2019
Come on Jaah, you must have tried something already. This is not your first question. Show your attempt.
jaah navi
jaah navi on 28 May 2019
I tried with the command randi([1,5], 1, 10) as i am unable to get the required result i posted the question.

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Accepted Answer

Rik
Rik on 28 May 2019
I can't think of a better solution, but you could try brute-forcing it with a while loop:
maxval=5;cols=10;
if maxval>cols
error('impossible combination')
end
result=randi(maxval,1,cols);
val_list=1:maxval;
while ~all(ismember(val_list,result))
result=randi(maxval,1,cols);
end

More Answers (2)

Renato SL
Renato SL on 28 May 2019
From
help randi
you will get the following:
R = randi([IMIN,IMAX],...) returns an array containing integer
values drawn from the discrete uniform distribution on IMIN:IMAX.
Since the numbers are drawn with uniform distributions, I don't think randi is what you should use. One clue is given in later lines:
The arrays returned by randi may contain repeated integer values. This
is sometimes referred to as sampling with replacement. To get unique
integer values, sometimes referred to as sampling without replacement,
use RANDPERM.
Perhaps try using randperm instead to have all 5 numbers everytime the command executes, as you expect.
PS.
Maybe this is not the most efficient answer, but try using this line:
[randperm(5,1) randperm(5,2) randperm(5,3) randperm(5,4)]

KSSV
KSSV on 28 May 2019
[randi([1,5], 1, 5) randi([1,5], 1, 5)]
  2 Comments
Rik
Rik on 28 May 2019
This is not guaranteed to contain all numbers 1:5.
jaah navi
jaah navi on 28 May 2019
Ok.For repeating 5 numbers with respect to 10 columns i can use your command.
But if i need to repeat 100 numbers with respect to 300 columns i am unable to use the above command.
So i need to have to a common command which gets executed for all possibilities
Could you please help me on this.

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