Count if a vector has at list one element greater than zero

Hello everyone, I'm looking for a way to update a count if a vector has at least one element greater than zero.

I mean for example:

count=0;
v=rand(100,1); 
%check if v has at least one element greater than zero, if yes 
count=count+1;

Thank you

[Enrico Gambini]

I think i got a part of the answer

if(any(v)) %returns true if any of the elements of v is nonzero
    count=count+1;
end

Answer 1

[Jorg Woehl]

count = sum(v>0)

The expression v>0 creates a logical array of 1s and 0s, with a 1 for every element of v that is greater than zero. Summing all values in the logical array therefore gives the total number of elements greater than zero.

(By the way, the rand function only generates positive numbers between 0 and 1, so to create random numbers between -1 and 1, you would use 1-2*rand.)

[Enrico Gambini]

Thank you for the answer, but in my case i don't want to have a count of all the vector elements which are greater than zero. I'd like to count if and only if at least one element of the vector is greater than zero.

For example if i have the vector v=[0,20,10,0,100] there's at least one element greater than zero and so i count.

[Jorg Woehl]

I see - in this case, using the any function like you suggested would be the way to go. Test if at least one element of v is greater than zero and then increase the count variable accordingly:

if (any(v>0)) % returns true if at least one element of v is greater than zero
    count=count+1;
end

[Stephen23]

Simpler:

count = count + any(v>0);