How to set the boundaries?

Hello,
Please help me :)
I have a row with 0 and 1 (they are used for classification) and its indexes. I need to get just the boundaries for the interval of 0 or 1. How I can do it?
For example this is what I have:
targets=[0 0 0 1 1 1 0 0 1 1 0 0 0]
index= [0 1 2 3 4 5 6 7 8 9 10 11 12]
This is what I want to get:
targ= [0 1 0 1 0]
boundindex=[0 3 6 8 12]
Thanks!

 Accepted Answer

Try this:
boundindex = [0, find(abs(diff(targets)))]
The only difference is that my array gives 10 as the final value, because 10 is where the final group of 0's starts. Not sure how you got 12. Why do you want 12 and how did you arrive at that value?
Not sure what the point of targ is or why it's needed so I didn't compute it.

4 Comments

Ra Ga's "Answer" moved here:
I think it was mine mistake. Well, it works for these indexes. But if my indexes which describe the bFor example this is what I have:
targets=[0 0 0 1 1 1 0 0 1 1 0 0 0]
index= [0 15 20 35 45 50 60 75 80 99 101 111 102]
How to get boundaries from these indexes?
Thanks a lot!
I think boundindex would be the same. Now what are all the outputs that you want to get from this, and what rules are you applying to get them?
Ra Ga
Ra Ga on 18 Mar 2018
Edited: Image Analyst on 18 Mar 2018
I have this:
targets=[0 0 0 1 1 1 0 0 1 1 0 0 0] % describe peaks
index= [0 15 20 35 45 50 60 75 80 99 101 111 120] % index of the peak
I have the row of peaks (PPG signal). 0 - one class, 1 - another class.
What I want to get just bound of the classes, not for each peak. Lets say that first three peaks belong to 0 class and other three to 1 class. So, I want to remove middle values.
This is what I want to get:
targ= [0 1 0 1 0]
index= [0 35 60 80 101]
Try this:
targets=[0 0 0 1 1 1 0 0 1 1 0 0 0] % describe peaks
index= [0 15 20 35 45 50 60 75 80 99 101 111 120] % index of the peak
startingIndexes = [0, find(abs(diff(targets)))]
boundindex = index(startingIndexes+1)
targ = targets(startingIndexes+1)
Shows in command window:
boundindex =
0 35 60 80 101
targ =
0 1 0 1 0
just as you requested.
Also read this how to format your code so I don't have to keep fixing your code formatting.

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More Answers (1)

Ra Ga
Ra Ga on 18 Mar 2018
There were some mistakes in my second answer. I need some help to the last question.

2 Comments

I don't know what to do. What is your "second answer"?
Why is the code I gave in my last comment not what you want? It gave what you said you wanted.
I see your answer at the moment. Previous it looks different. Thank you. It helped me!

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on 18 Mar 2018

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on 18 Mar 2018

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