Problem with find and logical array

Hi,

I have a matrix with the values : A = [260,343; 344,433; 434,530; 531,631; 632,723];

where A(:,1) is the lower range and A(:,2) = upper range for each row. I am trying to find the index of A where a number may exist within the upper and lower range.

For ex. I tried B = (443 > A(:,1) & A(:,2) > 443) to check in which row the number 443 would lie, but got the ans as 0, even though when B comes as = [0,0,1,0,0]. I performed index = find(B),

I am probably doing something stupid. What am I doing wrong?

Thanks, Urvashi

[José-Luis]

I don't understand. The function seems to do exactly what you want it to do, according to your description.

[Urvashi]

I know. I will download 'find' again. May be it's a problem with my function

[Geoff Hayes]

What do you mean by "download 'find' again"? Are you using a different version of find from the built-in one?

Answer 1

[Sara]

You could do:

   B = find(443 > A(:,1) & A(:,2) > 443);

B is the row or rows where the condition is satisfied.

[Urvashi]

I did that too, and still got the answer as B = 0. There might be something wrong with the function 'find' in my version. I should probably download it again.

[Sara]

Yeah, could be, because everybody here is getting the right result.

Answer 2

[Image Analyst]

I don't see any problem:

A = [260,343; 344,433; 434,530; 531,631; 632,723]
targetValue = 443
logicalRowsInRange = (targetValue > A(:,1) & A(:,2) > targetValue) 
rowInRange = find(logicalRowsInRange)

A =
   260   343
   344   433
   434   530
   531   631
   632   723
targetValue =
   443
logicalRowsInRange =
     0
     0
     1
     0
     0
rowInRange =
     3

Answer 3

[Urvashi]

Yeah, thanks a lot. It worked. I had missed a ) in one of my previous statements of find, so find ended up being an empty matrix. And I didn't realize that the variable find was generated as there was a huge list of variables being generated during the program run.

My bad. Really, my bad.