Question

I’m trying to examine on which rows a particular value is located in a cell, then retrieve the rows in those positions from another cell and put them into a variable.

My data is like:

1x4 Cell =

     A           B          C            D           %Cell labels for clarity
{10x1 Cell} {10x1 Cell} {10x1 Cell} [10x1 Double]

   B          blue          M           4.78
   R          red           N           6.43
   R          red           N           6.89
   B          blue          M           7.99
   B          blue          M           5.87
   B          blue          M           4.78
   R          red           N           6.43
   R          red           N           6.89
   B          blue          M           7.99
   B          blue          M           5.87

So for example, it would go like this: 1) search for the rows on which "blue" is located in B, 2) “blue” is found to be in rows 1, 4, 5, 6, 9 and 10. Then 3) extract rows 1, 4, 5, 6, 9 and 10 from another datacell, C, to a new variable.

As far as I am aware, logic operations like == may not be sufficient for what I want to do. Which functions should I be looking at to achieve this?

Thanks

Answer 1

Try this:

C(cellfun(@isequal, B, repmat({'blue'},10,1)))

Explanation:

• repmat makes a cellarray of ‘blue’ with a size of B
• isequal compares the content of two cells
• cellfun repeats for all cells and returns logical column
• C(...) indexes C with this column and returns matching rows

Regards