Random selection of n values from a vector - which function should I use?

I have a vector with twenty unique values from 1 to 20. I would like to select randomly two values from my vector. Which option should I use? Is there some difference between the functions attached below?

randperm

A = [1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20];
y =  A(randperm(20,2));

randsample

y = randsample(20,2);

datasample

y = datasample(A,2);

Answer 1

[Walter Roberson]

randsample() requires the Stats toolbox, and has more options such as selection with replacement.

Since your source is [1:20], you can simplify your randperm version to just

y = randperm(20,2);

but if it did not happen to be consecutive integers you could use the form you did,

A = 1:20;
y = A(randperm(numel(A),2));