Index a series of integers in a column of matrix

I am trying to find a function that will produce what row a series of numbers are together. For example in a column of the following:

T2 = [2 7 4 5 1 0 1 3 1 5 6 7 4 7 2 7]'

I would like to find which row there is a specific transition between 2 and 7 and vice versa. I have used the find(T2 == 2 & 7) function, however, that produces the location of every single location where the integer is exactly equal to 2 and 7.

Any suggestions?? Thank you!

Answer 1

[Star Strider]

I am not sure what you want.

Try this:

T2 = [2 7 4 5 1 0 1 3 1 5 6 7 4 7 2 7]';
Idx = strfind(T2', [2 7])
Out = T2([Idx(:) Idx(:)+1])

producing:

Idx =
     1    15

Out =
     2     7
     2     7

[Cheyenne Contreras]

This is exactly what I was looking for! Thank you!

[Star Strider]

As always, my pleasure!

[Cheyenne Contreras]

# Node

185 7

185 2

185 0

185 2

185 7

Hello,

Extending on this line of code, I need to determine the location of of 2 OR 7 when they are next to each other in the string. In the previous code, it was finding the occurance of the first location when 2 was before 7 and vice versa. Does anyone know if there is code to determine the second location regardless of order?

Thank you!

[Star Strider]

A slight change in the earlier code:

T2 = [2 7 4 5 1 0 1 3 1 5 6 7 4 7 2 7]';
Idx1 = strfind(T2', [2 7]);
Idx2 = strfind(T2', [7 2]);
Idx = [Idx1(:); Idx2(:)]
Out = T2([Idx(:)  Idx(:)+1])

produces:

Idx =
     1
    15
    14

Out =
     2     7
     2     7
     7     2

Note that you can use ‘Idx1’ and ‘Idx2’ separately, if you want specifically to index ‘[2 7]’ and ‘[7 2]’. I combined them here for convenience.