Generate random integer

Hi,

Can anyone help me to generate several strings of random integer ? In each string, there must be 5 integers generated which the number are in between 1 and 484. let say i wanna have 5 strings of the number. below is the example of the matrix that i need.

random number = [ 4 56 32 75 103; 47 84 302 400 27; 96 187 255 33 14; 387 293 135 34 73; 165 243 93 142 65 ]

Thanks in advanced.

nurul

Answer 1

[Walter Roberson]

ceil(484 * rand(5,5))

Note that this has the possibility of generating the same number multiple times. There are slightly different techniques if you require them to be unique along rows or columns.

[Nurul]

thanks for your answer as this is what i need for this time. But, what are the technique if i want the number to be unique in each rows and column?

[Walter Roberson]

The technique that is often used to satisfy uniqueness is to use randperm() to select the elements. Roger Stafford has a much more efficient technique, though; unfortunately I don't understand his algorithm. See for example http://www.mathworks.com/matlabcentral/newsreader/view_thread/149228

I do not recall at the moment the techniques for ensuring that values are unique in both their row and column and yet allowing the value to occur in a different place in the matrix. If the value has to be unique throughout the entire matrix then you just do it like the row or column case and then reshape the result.

Answer 2

[Sahan]

you can use randint function

   test = randint(5,5,[1 484])

[Walter Roberson]

Note that randint() is part of the Communications Toolbox, and will be removed in the future; randi() is the recommended replacement.