find same numbers in a row

Hello masters of MATLAB,

I am writing a script for a assigement of my study. I have a signal where I have to find places where 30 samples in a row are 0 or 1. The true or false are if the player is higher or lower than the walkingspeed of a player.

How could I find these sports. It is plotted in a line graph with at the x-axis the time and at y-axis the speed of the player.

Can someone help me?

[Adam]

doc diff

can give you the locations at which 0s change to 1s and vice versa. You can then use these locations to find when the relevant indicators are 30 samples apart.

[twan Zwetsloot]

If you get this vector as underneath. You want to only have the one that are more or equal to five in this example. Do you know how to solve this?

1

1

1

0

0

1

1

0

0

0

0

0

1

1

1

1

1

1

1

1

1

[Image Analyst]

As I showed, you can use regionprops(). But you have not said exactly what you want as the output. What EXACTLY do you want? A vector with only the long stretches in there? The location of the 1's? The location of the starting index of each long stretch? What?????

Answer 1

[Guillermo Rubio Gomez]

Assuming you have the time vector and the 0 and 1 vectors, to obtain the times corresponding to 0's and 1's:

ceros_time = t(y==0); % Vector with times correponding to 0's in the y vector
ones_time = t(y==1); % Vector with times correponding to 1's in the y vector

Answer 2

[Image Analyst]

You can do this if you have the Image Processing Toolbox:

props = regionprops(yourSignal, 'PixelIdxList', 'Area');
allLengths = [props.Area]; % Get all lengths into a list.
% Extract only where they are 30 long or longer.
goodIndexes = allLengths >= 30;
props = props(goodIndexes);
% Print out where they start and stop
for k = 1 : length(props)
    fprintf('Run #%d starts at index %d and stops at index %d', k, props(k).PixelIdxList(1), props(k).PixelIdxList(end))
end