How to generate random numbers between two numbers without any specific number?

I want to generate random numbers between 2 and 33. But do not want a(i) number. a(i) can be a single number between 2 to 33.

Answer 1

[Walter Roberson]

valid_choices = setdiff(2:33, a(i));
random_choice = valid_choices(randi(length(valid_choices)));

[Walter Roberson]

This can be trivially extended to a list of values to avoid,

valid_choices = setdiff(2:33, a);
random_choice = valid_choices(randi(length(valid_choices)));

Answer 2

[per isakson]

"[...] without any specific number?" I don't understand that. However, try

>> 2 + rand*(33-2)
ans =
   26.8087 

>> 2 + rand(1,3)*(33-2)
ans =
   31.9115    6.8860   32.0884

In response to comment

Try

>> num = one_random_number( 2, 33, [3,4,5,6,7,8] )
num =
   24.5963
>> num = one_random_number( 2, 33, 5 )
num =
   22.1580
>>

where

function   num = one_random_number( lower, upper, exclude )
    num = exclude(1);
    while any( num == exclude )
        num = lower + rand*(upper-lower);
    end
end

Add some error checking to the code and be prepared for comments regarding tests for equal on floating point numbers. Did you mean random whole number? If you did, replace

num = lower + rand*(upper-lower);

by

num = randi([lower,upper]);

[Arnab Pal]

I need one random number between 2 to 33, but 5 (say) should not come.

[Akira Agata]

You want to generate random integer between 2 to 33? Then, try randi([2, 33]).

If you want to generate random integer between 2 to 33 except 5, then the following will work.

r = randi([2, 33]);

while r == 5
  r = randi([2, 33]);
end

[per isakson]

I've updated the answer

[Arnab Paul]

time consuming

Answer 3

[NARAYAN SHARMA]

If you want to generate random real numbers between X1 to X2 except X3 then try the code written below

X1= 0;
X2=100;
X3=10;
total_number=1000;
for i=1:total_number
    Random_number=X1+ rand*(X2-X1)   
    while  Random_number==X3
             Random_number=X1+ rand*(X2-X1)   
   end
   Real_rand_number(i,1)=Random_number;
end

If you want to generate random integers between X1 to X2 except X3 then try the code written below

X1= 0;
X2=100;
X3=10;
total_number=1000;
for i=1:total_number
    Random_number=round(X1+ rand*(X2-X1))   
    while  Random_number==X3
             Random_number=round(X1+ rand*(X2-X1))  
   end
   Real_rand_number(i,1)=Random_number;
end

Answer 4

[Nardjim Hermann]

research randi,fix,round,ceil,floor functions

[Walter Roberson]

These do not in themselves answer the question. The question is not how to generate random integers: the question is how to do so while avoiding certain possibilities.