count number of ones in binary matrix

1  0  1
0     1
1  1  0

i need the output as : no of ones is 5

Answer 1

[Stephen23]

Simplest and most efficient answer:

nnz(A)

Answer 2

[Birdman]

A=[1 0 1;0 0 1;1 1 0];
cnt=sum(A(A==1))

Answer 3

[James Tursa]

Assuming you mean the sum of all elements:

A = your matrix;
result = sum(A(:));

If you really mean just the edges or something else, let us know.

Answer 4

[Image Analyst]

Do you really only care about the outer perimeter? So if the center is a 1, you want to ignore that? If so:

mTemp = m; % Make copy
mTemp(2, 2) = 0; % Make center zero so we won't count it if it's a 1.
numZeros = nnz(mTemp); % Effectively, count 1's in outer perimeter only.

Answer 5

[sumanth kumar]

function y = one(x)

c=0;

for i=1:length(x)

if(x(i)==49)

c=c+1;

end

end

y=c;

end

[Stephen23]

Although the function does not have any help or code comments, it appears that it was written to count the character '1' (which has a character value of 49) in a character vector, in which case the simple MATLAB equivalent would be:

y = nnz(x=='1')