How can I generate random numbers

I have along data series which contains 3451 elements. From this I want to select 1/3 rd of the elements for validation purpose and the remaining for test. How can I randomly make the selection randomly? Thanks .

Answer 1

[Image Analyst]

Use randperm(), as this demo illustrates:

% Define the number of elements to use.
numberOfElements = 3451;
oneThird = int32(floor(numberOfElements / 3));
% Get all the indexes scrambled in a random order.
randomOrder = int32(randperm(3451));
% Select a third of them for "Validation."
indexesForValidation = randomOrder(1:oneThird);
% Select the remainder of them for "testing."
indexesForTesting = randomOrder(oneThird+1:end);

[Ede gerlderlands]

Thank you...

[Ede gerlderlands]

Sorry I think Index for testing doesn't seems to work for me.

[Image Analyst]

I fixed a small bug. Try it now.

[Ede gerlderlands]

yes , it works tnx.