Thread Subject: return index of positive row

how to return the index of positive row?
For example,
A = [1 2 -3; 4 5 6; 7 9 -8];

I expect a function returenpositive(A) = 2;
because the second row of A are all positive numbers. thank you!

"Arthur Zheng" <hzheng7@gatech.edu> wrote in message
<g5jkl5$fiv$1@fred.mathworks.com>...
> how to return the index of positive row?
> For example,
> A = [1 2 -3; 4 5 6; 7 9 -8];
>
> I expect a function returenpositive(A) = 2;
> because the second row of A are all positive numbers. thank you!

You can do this yourself. Try it. What
does the expression

  A > 0

return?

Now, look at the functions all, and find.
Can you combine these functions to give
you the desired result?

John

"Arthur Zheng":
<SNIP a newbie conundrum...

> how to return the index of positive row?
> A = [1 2 -3; 4 5 6; 7 9 -8];

one of the solutions

     v=[1,2,-3;4,5,6;7,9,-8;10,10,10];
     r=find(all(sign(v)==1,2)).'
% r = 2 4

us