# finding a numeric pattern in an array

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Saikrishna on 27 Mar 2023
Commented: Saikrishna on 27 Mar 2023
Hi all,
I have a big numeric vector and I am trying to find a pattern in the vector.
Example:
my numeric vector = [11 5 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 11 2 31 5 1 2 11 2 31 5 1 2 11 2 31 5 1 2 11 2 31 5 1 2 11 2 31 5 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 11 2 31 5 1 2 11 2 31 5 1 2 11 2]
pattern : [1 2 3 4 5 *any numbers* 1 2 3 4 5 1 2 11 2 31]
I know strfind works well if I know the exact sequence of pattern. But for the above case I am unable to find the solution.

Stephen23 on 27 Mar 2023
Edited: Stephen23 on 27 Mar 2023
V = [11,5,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,11,2,31,5,1,2,11,2,31,5,1,2,11,2,31,5,1,2,11,2,31,5,1,2,11,2,31,5,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,3,4,1,2,3,4,5,1,2,3,4,5,1,2,3,4,5,1,2,11,2,31,5,1,2,11,2,31,5,1,2,11,2]
V = 1×133
11 5 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5
F = @(v) regexptranslate('escape',char(v));
P = sprintf('%s.*?%s',F([1,2,3,4,5]),F([1,2,3,4,5,1,2,11,2,31]))
P = '□□□□□.*?□□□□□□□□□□'
[X,Y,M] = regexp(char(V),P, 'start','end','match') % start & end indices, matched text.
X = 1×2
6 64
Y = 1×2
35 122
M = 1×2 cell array
{'□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□'} {'□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□□'}
Checking the matched content:
double(M{1})
ans = 1×30
1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 11 2 31
double(M{2})
ans = 1×59
1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5
Saikrishna on 27 Mar 2023
@Stephen23 excellent! Thank you :) that worked for me perfectly

Dyuman Joshi on 27 Mar 2023
Edited: Dyuman Joshi on 27 Mar 2023
vec=[11 5 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 11 2 31 5 1 2 11 2 31 5 1 2 11 2 31 5 1 2 11 2 31 5 1 2 11 2 31 5 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 3 4 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 1 2 11 2 31 5 1 2 11 2 31 5 1 2 11 2];
pat1 = 1:5;
pat2 = [pat1 1 2 11 2 31];
%Starting index of pattern 1
idx1=strfind(vec,string(pat1))
idx1 = 1×15
6 11 16 21 26 64 69 74 79 84 89 94 103 108 113
%Ending index of pattern 2
idx2=strfind(vec,string(pat2))+numel(pat2)-1
idx2 = 1×2
35 122
Any viable combination of elements of idx1 to idx2 will be the pattern i.e. 6-35, 11-35, 16-35, 6-122, 64-122, ...
A viable combination is idx1(m)<idx2(n)