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matlabhistogrambinningmatrix-indexing

Get bin edges from a histogram by index of the bin

I have a matrix m and plot a histogram of the third column. I search for the peak in the first 100 bins and get the frequency as a and the index of the bin as b. Now I need the edges of the bin with index b. How can I get them? 

nbins = 1000; 
histo = histogram(m(:,3),nbins,'Orientation','horizontal'); 
[a,b] = max(histo.Values(1:100))
Solution

  • I can think of two easy ways to do this:

    function q41505566
m = randn(10000,5);
nBins = 1000;

% Option 1: using histcounts:
[N,E] = histcounts(m(:,3),nBins);
disp(E(find(N(1:100) == max(N(1:100)),1,'first')+[0 1])); % find() returns the left bin edge

% Option 2: using BinEdges:
histo = histogram(m(:,3),nBins,'Orientation','horizontal'); 
[a,b] = max(histo.Values(1:100));
disp(histo.BinEdges(b:b+1));

    If you need an explanation for the "tricks" - please say so.