Hi @CramerRaoError1 : Further to @peng_liu 's comment. Effectively, it is the same as the following; say you want a random subset of size n.
1. Assign each row a random number (each Uniformly distributed between 0 and 1).
2. Sort the Rows by the Uniform number.
3. Take the top n rows as the random subset of size n,
There are other methods...but, they all boil down to each sample of size n having equal probability of being selected. So, in that sense, the methods are all equivalent.