Please explain the above commands,

a=[7 3 5; 6 2 1]; dd=find(a<4)

dd =

     3
     4
     6

How it is possible to display the 4 in that ans? and my condition is to find the <4 values in matrix a. But how it was display the 4 also?

Please anyone explain me...

Answer 1

[Mischa Kim]

Ramya, dd contains the position numbers of all elements in matrix a that are smaller than 4, which would be 3, 2, and 1.

 a =
     7     3     5
     6     2     1

The position number of the elements is counted sequentially row by row, and column by column:

     1     3     5
     2     4     6

If you want row and column indices use

 [r,c] = find(a<4)

[RAMYA]

Okay, yet I didn't get it exactly. bcoz, whenever I display the row and col indices, it displays the above,

a=[7 3 5; 6 2 1]; [r c]=find(a<4)

r =

     1
     2
     2

c =

     2
     2
     3
Sorry, I can't able to understand, could you explain it briefly? Bcoz, yet I getn't clear about the 4 in output dd.

[Mischa Kim]

MATLAB numbers matrix elements top-down (rows) and left-right (columns). So for matrix

a =
   7     3     5
   6     2     1

7 would be the first, 6 the second, 3 the third and 2 the fourth (4) element. That's the 4 you get in

 dd = find(a<4)
 dd =
     3
     4
     6

The first element in a that's smaller then 4 is 3, which is the third matrix element. The last one is 1, which is on position 6 in the matrix.

[RAMYA]

ya sir........ thank u :) i got it... thanks for your valuable reply :)