Find number of zeros in a part of a matrix

I need to find the number of zeros that are contained in a part of a matrix. For example if the matrix is [1 2 2 2 2 2 0 2 2 2 0 3 0 0 4 5 6 7 0 0 8] is there a fast way to get the number of zeros between the fifth and tenth element? In this case the answer would be 1.

Thank you!

Answer 1

[Evan]

A = [1 2 2 2 2 2 0 2 2 2 0 3 0 0 4 5 6 7 0 0 8];

numZeros = sum(~A(5:10));

Answer 2

[Image Analyst]

Three ways that I can think of off the top of my head:

data = [1 2 2 2 2 2 0 2 2 2 0 3 0 0 4 5 6 7 0 0 8];
numberOfZeros = length(data) - nnz(data)
numberOfZeros = sum(data==0)
numberOfZeros = nnz(~data)

[Image Analyst]

Note: this does the whole array because I think it's a dangerous assumption to look just between the 5th and 10th elements, which works well for your example but not in general.

Answer 3

[Sarumathi C]

How do I find the zeros locations in a array by using "for loop" and store in the new array matrix?

Example:

    [1 2 3 0;
     4 5 6 0;
     7 8 0 9.....]

I need the output like

[ 4
  4
  3]

It's a zeros Location

If zeros location is same,we should find the difference between the two rows...

Like,

In the above Matrix we have a 4. & 4 there is zeros locations are same so we should find out the difference between that two rows like

4-1=3; 
5-2=3....

So the output like

[3 3 3
 7  8  0  9....]

[Image Analyst]

Use find() and a for loop:

m=[1 2 3 0;
  4 5 6 0;
  7 8 0 9
  4 0 0 7
  0 5 0 0]
for row = 1 : size(m, 1)
  zeroLocations{row} = find(m(row, :) == 0)
end
celldisp(zeroLocations)

[Jan]

@Sarumathi C: Please open a new thread for a new question. This is better than hijacking an existing thread by attaching a new question in the section for answers. Thanks.