How to mark periods in my matrices?

Question

JamJan 2018-7-23

0
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此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/411762-how-to-mark-periods-in-my-matrices

编辑： jonas 2018-7-24

Hello,

Since I am new in Data Analysis, I need some help marking periods of consecutieve 1's.

for i=1:length(PD) 
for isessions=1:PD(i).TotSessionsVid
[PD(i).FakeMatrix(isessions).Random] = randi([0 1], 10000,4);
for iconfig=1:length(PD(i).FakeMatrix(isessions).Random)
if PD(i).FakeMatrix(isessions).Random(iconfig, :) == [1 1 1 1]
   PD(i).FakeMatrix(isessions).Random2(iconfig, :) = [PD(i).FakeMatrix(isessions).Random(iconfig, :), 1];
elseif PD(i).FakeMatrix(isessions).Random(iconfig, :) == [1 1 1 0]
   PD(i).FakeMatrix(isessions).Random2(iconfig, :) = [PD(i).FakeMatrix(isessions).Random(iconfig, :), 1];
elseif PD(i).FakeMatrix(isessions).Random(iconfig, :) == [1 1 0 0]
   PD(i).FakeMatrix(isessions).Random2(iconfig, :) = [PD(i).FakeMatrix(isessions).Random(iconfig, :), 1];
elseif PD(i).FakeMatrix(isessions).Random(iconfig, :) == [1 0 1 0]
   PD(i).FakeMatrix(isessions).Random2(iconfig, :) = [PD(i).FakeMatrix(isessions).Random(iconfig, :), 1];
else
   PD(i).FakeMatrix(isessions).Random2(iconfig, :) = [PD(i).FakeMatrix(isessions).Random(iconfig, :), 0];
end
end
end
end

This is my code and my goal is to find for example 5 (or as many as I want) consecutieve 1's in the 5th column of the Random2 FakeMatrices. How can I do that? I have tried && statements combined with if statements, but I believe this can be more efficient. Can anyone help me? I want to mark them as 'on'.

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jonas 2018-7-23

编辑：jonas 2018-7-23

A bit, can you just also specify the exact output you want for col 5?

JamJan 2018-7-23

for example: This could be the output of the Matrix:

col 1 col2    col3    col4  col5 col6
1  1  1  1 on
1  0  0  1 on
0  1  0  1 on 
1  1  0  0 off
0  1  0  0 off
0  1  0  1 off
0  1  1  0 off
0  0  0  0 off
1  0  0  1 on
0  1  0  1 on
1  0  0  1 on
1  0  0  1 on
0  0  1  0 off
0  1  0  0 off 
0  1  0  0 off
0  1  1  0 off

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Answer 1

jonas 2018-7-23

1
链接

此回答的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/411762-how-to-mark-periods-in-my-matrices#answer_330012

编辑：jonas 2018-7-24

If you have the image processing toolbox, you can use the function bwconncomp to find connected 1's. Using the example in the comments, this script finds segments where there are 3 or more consecutive 1's, and fills the output vector with 1's (indicating 'on')

CC=bwconncomp(M(:,5),4)
size(CC.PixelIdxList)
for i=1:numel(CC.PixelIdxList)
    if numel(CC.PixelIdxList{i})>=3
        out(CC.PixelIdxList{i})=1
    end
end

If you do not have the image processing toolbox, you can use this solution instead.

%%Find at least 3 consecutive 1's
target=ones(1,3);
pos = strfind(M(:,5)',target);
out=zeros(size(M(:,5)));
for i=1:numel(pos)
    out(pos(i):pos(i)+2)=1;
end

You can change the target to any number of consecutive 1's. You can also find other patterns, such as [1 0 1], but you will have to tweak the for-loop a bit.

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JamJan 2018-7-24

编辑：JamJan 2018-7-24

Thanks!!! However, it seems that it places 4 ones when it sees 4 consecutive ones? I think it then should be like this

%%Find at least 3 consecutive 1's
target=ones(1,3);
pos = strfind(M(:,5)',target);
out=zeros(size(M(:,5)));
for i=1:numel(pos)
    out(pos(i):pos(i)+2)=1;
end

Anyway, thanks this helps a lot!

jonas 2018-7-24