This question already has an answer here:
I have given list of numbers,
x=[x1, x2, x3, x4, x5, x6];
non_zero=find(x);
I want Matlab to randomly select anyone among elements of 'non_zero' at a time. I searched online but there is no such function available to provide my required results.
You could use the function randi to randomly select an integer from the set of valid indices.
x=[x1, x2, x3, x4, x5, x6];
non_zero=find(x);
index = randi(numel(non_zero));
number = x(non_zero(index))
Or, perhaps a bit more clear, first make a copy of x, remove the zero elements from this copy, and then select a random integer from the range [1 numel(x_nz)].
x=[x1, x2, x3, x4, x5, x6];
x_nz = x;
x_nz(x == 0) = 0;
index = randi(numel(x_nz));
number = x_nz(index)
To ensure that you do not get the same sequence each time, first call rng('shuffle') to set the seed for random number generation.
Have you considered randsample or datasample?
x = [1 4 3 2 6 5];
randsample(x,1,'true') % samples one element from x randomly
randsample(x,2,'true') % two samples
datasample(x,1)
% Dealing with the nonzero condition
y = [1 2 3 0 0 7 4 5];
k = 2; % number of samples
randsample(y(y>0),k,'true')
datasample(y(y>0),k)
After posting this answer, I found this excellent answer from @Rashid (linked by @ChrisLuengo). He also suggests considering if datasample(unique(y(y>0),k) is appropriate.
