How to generate a vector of random numbers whose total must be equal to 1?

I want to generate a random vector. if i add all the values in the generated vector, its sum should be equal to 1.

Answer 1

[James Tursa]

See this FEX submission by Roger Stafford:

https://www.mathworks.com/matlabcentral/fileexchange/9700-random-vectors-with-fixed-sum

[balaji]

Sir/Madam, I have tried just now in editor window as s = randfixedsum(1,3,1,0,1). but it shows unexpectd matlab expression while using it in editor window

[James Tursa]

You have your dimensions reversed:

s = randfixedsum(3,1,1,0,1);

The way you are doing it, you are requesting only one random number in each of three columns that sums to 1, and the internal algorithm is failing at that because it doesn't make sense.

[balaji]

No. I want 1 row having 3 values (column) (for example s = 0.5 0.3 0.2) whose sum should be equal to 1

[James Tursa]

... sigh ...

Then transpose the result:

s = randfixedsum(3,1,1,0,1)';