Grouping elements by conditions

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Amro Lulu
Amro Lulu on 21 Aug 2018
Commented: dani elias on 19 Nov 2020
I have an array [ 1 1.2 1.5 1.9 5 8 8.1 10 12 12.3 12.5]. I'm trying to group the elements that are within a window of length 1, so I get [ 1 1.2 1.5 1.9] [8 8.1] [12.3 12.5] How can this be done efficiently
  2 Comments
Matt J
Matt J on 21 Aug 2018
Will the grouped elements always be consecutive?
dani elias
dani elias on 19 Nov 2020
how can I use the same concept to group every 4 binary digit, for the case I have an array of 256 binary number,
example
a=[1 1 1 1 1 1 1 1 1 0 1 1 1 0 0 0];
to be in a form of
b=[1111;1111;1011;1000]

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Accepted Answer

Matt J
Matt J on 21 Aug 2018
Edited: Matt J on 21 Aug 2018
You could try this file
x=[ 1 1.2 1.5 1.9 5 8 8.1 10 12 12.3 12.5];
label = graph_connected_components(abs(x.'-x)<=1)
groupcell = splitapply(@(g){g},x,label)
  5 Comments
Amro Lulu
Amro Lulu on 29 Aug 2018
Hey Matt, I have a question related to this, what if I have a matrix x=[ 1 1.2 1.5 1.9 5 8 8.1 10 12 12.3 12.5; 1 5.3 2.1 5.4 1 6 2.1 45 23 14.3 13.4] And I need to group them the same way, however, only based on the first row, and the resulting group will include the corresponding elements from the second row, as
[ 1 1.2 1.5 1.9; 1 5.3 2.1 5.4] ..etc..
Thank you and I really appreciate it
Matt J
Matt J on 29 Aug 2018
Adapting Yuvaraj's answer,
x=[ 1 1.2 1.5 1.9 5 8 8.1 10 12 12.3 12.5; 1 5.3 2.1 5.4 1 6 2.1 45 23 14.3 13.4];
a=x(1,:);
Len=diff([0,find(diff(a)>1),numel(a)]);
S=mat2cell(x,2,Len)

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More Answers (1)

Yuvaraj Venkataswamy
Yuvaraj Venkataswamy on 21 Aug 2018
Edited: Matt J on 21 Aug 2018
This is your answer.
X=[ 1 1.2 1.5 1.9 5 8 8.1 10 12 12.3 12.5];
Len=diff([0,find(diff(a)>1),numel(a)]);
S=mat2cell(X,1,Len);

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