MATLAB: How to cut out specific segment from findpeaks function

findpeaks

Hi All,
I am trying to figure out how to cut out the specific segment of the signal where I draw the border using findpeaks function.
I am using example of findpeaks link below:
Example Link of findpeaks function
x = linspace(0,1,1000);
Pos = [1 2 3 5 7 8]/10;
Hgt = [4 4 2 2 2 3];
Wdt = [3 8 4 3 4 6]/100;
for n = 1:length(Pos)
    Gauss(n,:) =  Hgt(n)*exp(-((x - Pos(n))/Wdt(n)).^2);
end
PeakSig = sum(Gauss);
plot(x,Gauss,'--',x,PeakSig)
grid
1.png
Then, using findpeaks function, 
findpeaks(PeakSig,x,'Annotate','extents','WidthReference','halfheight')
title('Signal Peak Widths')
2.png
I want to cut the segment of the border into 3 segment.
4.PNG
The method I am thinking is find the X value corresponding the Y value, which is not an effective way to do it.

Best Answer

You can get the ‘Borders’ x-coordinates using: 
(Previous Code)
findpeaks(PeakSig,x,'Annotate','extents','WidthReference','halfheight')
title('Signal Peak Widths')
Ax = gca;
Kids = Ax.Children;
Borders = Kids(1:2);
Line = Borders.XData;
You have to search the ‘Axes.Children’ result manually to find the ‘(Border)’ elements. There appears to be no way to get them automatically, or even to specifically search for a ‘Line (Border)’ or ‘Border’ entry in the ‘Kids’ variable. (There may be a way, but it would take more patience than I have tonight to find it. I’ve tried every cell and structure addressing approach I can think of or can find in the documentation, including using strcmp and related functions, and couldn’t get a good result.) It would be very nice if this was more straightforward.
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