help n=12 for I=1:n p(I) =rand p(I) =28×p(I) p(I)=ceil(p(I)) end I need to put constraint on this code must be theres no redanandnt values ..so if n=28 p will be all the numbers from 1:28 but in random

 n=12 
for I=1:n  
p(I) =rand
p(I) =28×p(I) 
p(I)=ceil(p(I))
end 
I need to put constraint on this code must be theres no redanandnt values ..so if n=28 p will be all the numbers from 1:28  but in random

[Adam]

Please keep code in the body of the question not in the title. The title should be a short description of the problem.

Also please use the {} Code block to include formatted code.

Answer 1

[Star Strider]

‘I need to put constraint on this code must be theres no redanandnt values ..so if n=28 p will be all the numbers from 1:28 but in random’

The easiest way is to use the randperm function:

n = 12;
p = randperm(n);

[maha ismail]

this not work cause the numbers will be between 1:12 but I need to generate 12 integer elementes there values between 1 to28 but at random like this [3 ,26 ,1 ,19 ,3 ,12 ,2, 15,9 ,11,23,18] without any repeated values

[Adam]

Ah yes, I thought there must be some builtin way of doing this, but I just couldn't remember it!!

[Adam]

randperm( 28, 12 )

would be what you would need to get 12 distinct values between 1 and 28.

[Star Strider]

@Adam — Thank you for your Comment!

Our friendly randperm appears frequently in Answers. That’s how I learned about it, since I don’t otherwise need to use it that often.

[Star Strider]

@maha ismail — If you don’t have randperm, use Matt Fig’s File Exchange contribution COMBINATOR.

Answer 2

[Adam]

Something like this would work:

nums = 1:28;

n = 28;

p = zeros(1,n);

count = numel( nums );

for i = 1:n
  idx = randi(count);
  p(i) = nums( idx );
  nums( idx ) = [];
  count = count - 1;
end

Not necessarily the most efficient way of doing it, but it will guarantee uniqueness so long as n is at most 28 (or whatever value you set as the maximum of nums.

[maha ismail]

my matlab is version 6.5 doesn't not have randi or randperm instructions ..I have only rand code can you rewrite the same program but with rand instruction?

[Adam]

replace:

randi( count )

with

round( rand( count ) * n )

and I think that should give you the correct answer.