Vector inside another vector

Hi! I have a vector S = [0 1 2 3 4 ... 30]' and now i want to create another vector U that is equal to 0 if K<S and equal to S if K>=S. In my exercise K=15.

I did this:

U1=zeros(30,1);

U1(15,30)=S;

Can you please help me? Thanks

[Adam Danz]

So U will always be a column vector the same size as 'S' and it will always be either full of 0s or it will match the "S" vector (depending on the value of K which will always be a single number (scalar)). Is that correct?

[Alex Sune]

Your problem is not difficult. You just need to take a look to logical indexing in Matlab. For example:

logical indexing

matrix indexing

[José Campelo]

Correct. Basically what I want is that U be a column with 0 until the 14th position and then 15, 16, 17 etc until 30.

Answer 1

[Adam Danz]

S =(0:30)';
k = 15; 

U = S .* (S>=k);

Answer 2

[madhan ravi]

People don’t do homeworks here. Index K>=S to U1 lhs and S rhs by equating against each other. Since it’s your homework see Alex’s links above and experiment.

[Adam Danz]

My homework detectors didn't go off on this one.

[madhan ravi]

XD sometimes it doesn’t even in mine, maybe a bug xd.