Finding minima
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I have a data file with few valleys (minima). is there a way to find all the x coordinates corresponding to each minimum y value?
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Accepted Answer
Matt Tearle
on 15 Feb 2011
If you want fancy, take Walter's advice and search FEx. If you want quick and dirty:
x = 1:50;
y = sin(5*x);
idx = [false, y(3:end)>y(2:end-1) & y(2:end-1)<y(1:end-2), false];
xmin = x(idx)
plot(x,y,'o-',xmin,y(idx),'rx')
7 Comments
Matt Tearle
on 16 Feb 2011
Hah. Actually I just hunt the intartubes looking for places to apply logical indexing! ;)
More Answers (3)
Walter Roberson
on 15 Feb 2011
There is are a fair number of postings, and several Matlab File Exchange contributions, for finding peaks, which you could either modify or apply to the negative of your data.
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Graig
on 15 Feb 2011
1 Comment
Matt Tearle
on 16 Feb 2011
To help others who might have the same question, it would be great if you could vote for and/or accept answers that you think should be given prominence. Thanks.
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