How do you get Matlab to return a value for how many 1's are in a vector containing just 1's and zeros

Like if i have greencars=[11111111000000000000] how to i get Matlab to count how many ones there are?

Answer 1

[Babak]

 >> greencars=[1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0]
 >> numer_of_ones = sum(greencars)

Answer 2

[Adrian Jimenez-Galindo]

You can use Count(greencars, '==1') Hope this helps.

Answer 3

[Azzi Abdelmalek]

a=[1 0 1 1 0 0 0]
numel(find(a))

Answer 4

[Walter Roberson]

nnz(greencars)