how to use the randi function to perform random numbers provided that no random number results are repeated or are not the same?

i want to do random numbers

phi = 1: 4 looping using the randi function.

I want each iteration not to come out the same number

so

iteration 1

randi (phi) = 3

iteration 2

randi (phi) = 1

iteration 3

randi (phi) = 4

iteration 4

randi (phi) = 2

I don't use the randperm function because what I want the output of the random result is one number.

how is the solution?

Answer 1

[Walter Roberson]

so_far = [];
for count = 1 : 4
    trial = randi(4);
    while ismember(trial, so_far)
        trial = randi(4);
    end
    randi_phi(count) = trial;
    do something with trial
end

However, there is seldom a good reason to do this. Instead do

randi_phi = randperm(4);
for count = 1 : 4
    trial = randi_phi(count);
    do something with trial
end

[Muhammad Sam'an]

thanks very much

[Walter Roberson]

There is another method:

available = 1:4;
for count = 1 : length(available)
    used_idx = randi(length(available));
    trial = available(used_idx);
    available(used_idx) = [];
    randi_phi(count) = trial;
    do something with trial
end

[Muhammad Sam'an]

let

c=[10 2 20 11

12 7 9 20

4 14 16 18 ];

s=[15

25

10 ];

d=[5 15 15 15 ];

[m,n]=size(c );

pop_size=25

gen_iter=100

phi=1:12

for ii=1:pop_size

randi_phi = randperm(length(phi ))

for count = 1 : length(phi )

count

k= randi_phi(count )

i=[1+mod((k-1),m )]

j=[1+mod((k-1),n )]

x(i,j)=min(s(i),d(j ))

s(i)= s(i)-x(i,j )

d(j)= d(j)-x(i,j )

end

end

I want to find x (i, j) until the loop pop_size = 25 but my math lab code results in x (i, j) = (m, n) = 0, even though if the loop uses length phi the value x (i, j) comes out or not zero. if anyone can help my mathlab code this. ? This I use a new genetic algorithm at the chromosome initialization stage

How to generate nonzero x (i, j) values using loop function 1: pop_size?