MATLAB: Picking a random row of a matrix

random row selection

Hello, I have a matrix Y that's nx2. Say in this case n=5. (n can only take the values 3,5 or 8 but I guess that doesn't matter)

Y =

9 2

10 2

9 3

9 4

10 4

I want to randomly choose on of these rows so I can use them as coordinates!

Many thanks,

Phill

k = randi(size(Y,1)); % the random row index

Y(k,:) is the random row

idx1 = find(A==1);
idxkeep = randperm(numel(idx1),how_many_you_want);
idx12keep = idx1(idxkeep);

Is something like this what you want? Randomly distributed values from X but staying in same column?

X = whatever
rows = desired number of rows of the result B
[M,N] = size(X);
B = X(bsxfun(@plus,randi(M,rows,N),M*(0:N-1)));