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How do I create a single random number between two values?

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I need to create a value for one of my variables in a loop which will run ten times. I need it to be between two set values, e.g. 1e3 and 9e3. Sorry for what is probably a very basic question but I am new to matlab.

Accepted Answer

Wayne King
Wayne King on 22 Mar 2012
Does it have to be an integer, or any number between 1e3 and 9e3?
For the former:
Int = randi([1e3 9e3],1,1);
For the latter:
R = 1e3+8e3*rand(1,1);
The preceding line gives you a uniform random number between 1e3 and 9e3.
Marvin on 22 Mar 2012
Thanks, I tried changing the seed and it didn't seem to work, the problem was that I was changing the seed at the beginning of the program, not inside the loop! Silly mistake. Thanks for all the help!

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More Answers (3)

Image Analyst
Image Analyst on 22 Mar 2012
The help facility is always a good place to start. If you had searched the help for rand, you would have seen the very first example:
Example 1
Generate values from the uniform distribution on the interval [a, b]:
r = a + (b-a).*rand(100,1);
Image Analyst
Image Analyst on 13 Mar 2023
@Andrew Sol Since they will not be there (infinitesimally small chance) if you're just getting random numbers, you will have to add them in manually: Somthing like:
% Generate values from the uniform distribution on the interval [a, b]:
a = 5;
b = 10;
numElements = 7;
r = a + (b-a).*rand(numElements,1);
% Add in the max and min
r = [a; b; r];
% Scramble the array so they are not at the beginning
scrambledIndexes = randperm(numel(r));
r = r(scrambledIndexes)
r = 9×1
7.1316 10.0000 9.8263 6.0645 6.5554 7.7677 7.3234 5.0000 5.1012
Andrew Sol
Andrew Sol on 13 Mar 2023
@Image Analyst Thank you very much for your answer! it's really not that complicated

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Aldin on 22 Mar 2012
It's very helpful.

Nisha Bharti
Nisha Bharti on 12 Jan 2022
To generate a random number between [a,b]:
r = a + (b-a)*rand();
To generate N numbers:
r = a + (b-a)*rand(1,N);


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