# random no.

Asked by huda nawaf on 18 Mar 2012

hi, can i get random no. in specific range ?

between 19 , -19

thanks

## 1 Comment

Oleg Komarov on 18 Mar 2012

Yes, you can.

## Products

No products are associated with this question.

Answer by Image Analyst on 18 Mar 2012

You didn't read the help on rand(), did you? If you had, you would have seen the answer to your question as the very first example:

```Example 1
Generate values from the uniform distribution on the interval [a, b]:
r = a + (b-a).*rand(100,1);
```

Needless to say, a=-19 and b = 19 in your case, and 100 is the number of random numbers to be generated, or:

```r = -19 + 38 .* rand(100, 1);
```

## 1 Comment

Jan Simon on 18 Mar 2012

While the solution in easy, not to say trivial, the suggestion to read the documentation is an will be valuable. +1

Answer by the cyclist on 18 Mar 2012

Depending on whether you want to draw from a discrete or a continuous distribution, you will likely want to use either the randi() or unifrnd() function.

Answer by Sean Lawson on 18 Mar 2012

naively, this works: 38*(rand-0.5)

As Sean Lawson said in the above comment, using -19+38*rand will generate a random real number in the range (-19 19)

to generate random integers use

randi ([lower_limit upper_limit],a,b,c...)

which generates an axbxcx..... random integer array in the range (lower_limit upper_limit)