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Cycle counting from 0

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stefan
stefan on 11 Dec 2019
Commented: stefan on 14 Dec 2019
I have a matrix [ 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 1 0 0 0 0] for exemple
I'd like to have an outing:
2 x 4 "0" in succession
2 x 2 "0" in succession
1 x 3 "0" in succession
How to program it
Thank you.

  2 Comments

Image Analyst
Image Analyst on 11 Dec 2019
I have no idea what you want. What is an "outing"? Do you mean output? If so, what is the output array you want? I can't tell from your word descriptions. Type it out in numbers like you did for the input matrix.
Stephen Cobeldick
Stephen Cobeldick on 12 Dec 2019
stefan's "Answer" moved here:
With this matrix : [ 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 1 0 0 0 0 1 1 1 1 1 0 0 0 0 0 ]
I would have liked to have this matrix :
|5 2|
|6 1|
|4 1|
With the 1st column the number of successive 0
With the 2nd column the number of the sequence
thanks

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Accepted Answer

Stephen Cobeldick
Stephen Cobeldick on 12 Dec 2019
Edited: Stephen Cobeldick on 12 Dec 2019
>> M = [0,0,0,0,0,1,1,1,1,1,1,1,1,1,1,1,0,0,0,0,0,0,1,1,1,0,0,0,0,1,1,1,1,1,0,0,0,0,0];
>> D = diff([false;M(:)==0;false]);
>> L = find(D<0) - find(D>0);
>> [U,~,X] = unique(L,'stable');
>> V = histc(X,1:max(X));
>> Z = [U(:),V(:)]
Z =
5 2
6 1
4 1

  7 Comments

Show 4 older comments
stefan
stefan on 14 Dec 2019
Diff isn't the good fonction :
from 2 to 3 and from 3 to 4, I don't have the couples (1,2) and (2,3). I just know that there are passages from an N value to an N+1 value.
Stephen Cobeldick
Stephen Cobeldick on 14 Dec 2019
"I have a vector that can have values from 1 to 15. I would like to know the number of times for all the possible changes: for example:"
from 1 to 2
from 2 to 11
from 14 to 3
....
None of your provided data includes the values 11 or 14, so you are asking me to help you on an unknown algorithm with unknown data. Sorry, but my magic crystal ball is not working today.
"from 2 to 3 and from 3 to 4, I don't have the couples (1,2) and (2,3)."
Well, that makes two of us, because I don't have them either! Nor do you explain what they are, or how they relate to 1, 2, 11, 14, and 3 from your previous comment, or the binary data of your original question.
One clear explanation of the method/algorithm (complete with input and output example data) would actually mean that you get the help that you are looking.
stefan
stefan on 14 Dec 2019
it's a new question.
For example with this matrix:[1 1 1 1 12 12 2 3 2 3 4 5 2 1 10 13 13 14 14 14 14 ]
in output, I would have liked to have as an output vector:
1 12 1
12 2 1
2 3 2
3 1 1
3 4 1
4 5 1
5 2 1
2 1 1
1 10 1
10 13 1
13 14 1
with :
1st column: 1st number
2nd column: 2nd number
2nd column: number of times we have the couple (1st number, 2nd number)

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More Answers (1)

Akira Agata
Akira Agata on 12 Dec 2019
How about the following?
x = [0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 1 0 0 0 0 1 1 1 1 1 0 0 0 0 0];
str = num2str(x')';
c = regexp(str,'0+','match');
len = cellfun(@numel,c);
output = [(1:max(len))', accumarray(len',1)];
The result becomes like this:
>> output
output =
1 0
2 0
3 0
4 1
5 2
6 1

  2 Comments

Stephen Cobeldick
Stephen Cobeldick on 12 Dec 2019
stefan's "Answer" moved here:
that's not what I expect:
if I look at the matrix:
there are 2 sequences with 5 consecutive zeros
there is 1 sequence with 6 consecutive zeros
and there are 1 sequences with 4 consecutive zeros
the output matrix is:
5 2
6 1
4 1
Akira Agata
Akira Agata on 12 Dec 2019
You mean, the order is also important?
My output is same as what you expected, except the order of rows and including 0 sequence cases (such as 1~3 consecutive zeros).

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