Counting zeros

Question

1 个投票

Hi,

I would like to know how to calculate the number of zeros in an array and stop when the array value is one.

Example: a = [0 0 0 0 1 1 1 0 0 0]

here, there are 4 zeros before it meet array value of one.

then, let say I convert binary to RGB, 0=green and 1=red. The same thing goes here...how I want to calculate green pixel before it meet red pixel.

Anybody can give any idea. Thank you in advanced.

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marlina 2011-8-15

Let say if 0 remain black, only 1 turn to green. How to calculate black pixel before it meet the first pixel of green?

Answer 1

dhyun 2011-8-15

1 个投票

one method you could use is to find the first position where a == 1 and then subtract 1 from it:

num_zeros = find(a == 1, 1) - 1;

Paulo Silva 2011-8-15

find(diff(a)) %gives two index values, green to red and red to green

marlina 2011-8-15

Thanks,

I tried it but some error occurred.

Let say if 0 remain black, only 1 turn to green. How to calculate black pixel before it meet the first pixel of green?