Find a specific array within a larger array

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Hi all,
I am struggling with a problem. I have a large array, for example a = [11 12 13 14 15 16 13 14], and I want to find the index for a specfic sub sequence eg. b = [13 14 15]. So in this example I would want the index of 3 to indicate the position that b started in a. I dont want to know the indices of a that any number within b, i instead need them to be specifically in the order b, ie I dont care about the last two 13 14 numbers in a as it isnt the entirety of b.
I know I could simply do a loop that checks b against a subset of a and loops throughout the whole of a but this seems a little ineffectient if a is very big, (in my acutal code a is many 100,000's of numbers in length).
Is there a more efficent way, any help is appreiacted.
Thanks
J
  2 Comments
Dyuman Joshi
Dyuman Joshi on 28 Nov 2023
Moved: Dyuman Joshi on 28 Nov 2023
a = [11 12 13 14 15 16 13 14]
a = 1×8
11 12 13 14 15 16 13 14
b = [13 14 15]
b = 1×3
13 14 15
strfind(a, b)
ans = 3
Dyuman Joshi
Dyuman Joshi on 28 Nov 2023
Moved: Dyuman Joshi on 28 Nov 2023
Ah, it seems that I'm just a little late to the party.

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Accepted Answer

james ingham
james ingham on 28 Nov 2023
Sorted it! strfind does excatly what I need. I didnt inital consider this as I wasnt handling strings but it turns out that doesnt matter.

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