peaks for various graphs?

Forum|Forum|15 years ago
December 4, 2010
3 replies
7902 views

Hi,

im having trouble with finding the peaks of a various data sets.

im attaching 3 data sets.. is there any way that the peaks can be found for them?

im thinking of smoothing the data first using supsmooth and then it will be easier. so im attaching the matcad 11 file and im also adding some explanation within it.

update:

searched google and came accross this. its one of the sample files

http://support.mathsoft.com/support/mcad8/Examples/Locate_peaks.mcd

but its not there anymore.. does anyone know where can I get it? or is it even what im looking for

Message was edited by: UKMan

Statistics_Analysis

Best answer by RichardJ

Here's another approach. I've posted these functions before I think, but I don't recall which thread (and can't be bothered to search for it!). These are newer versions though, so if anyone has the old ones they should replace them.

As a note, if you choose the window as 10 and the threshold as 5% it will find the two peaks in the unsmoothed data, in all three cases. For data set 1 it finds only the higher peak in the doublet. If you actually wanted to find both peaks in the doublet you could change the window size to 4.

S

StuartBruff

23-Emerald V

very primitive method that relies upon having reasonably smooth data. haven't got time to find a 'proper' method, so this is just a top of the head thing.

Stuart

1_peaks-mcd.zip

S

StuartBruff

23-Emerald V

Of course, if I had any brains then apart from using a proper technique, I would have embedded the smoothing function within the peak detector.

Stuart

1_peaks-mcd.zip

M

MikeArmstrong

1-Visitor

Lovely work, great explanatory worksheet.

Mike

R

RichardJ

Answer

19-Tanzanite

Here's another approach. I've posted these functions before I think, but I don't recall which thread (and can't be bothered to search for it!). These are newer versions though, so if anyone has the old ones they should replace them.

As a note, if you choose the window as 10 and the threshold as 5% it will find the two peaks in the unsmoothed data, in all three cases. For data set 1 it finds only the higher peak in the doublet. If you actually wanted to find both peaks in the doublet you could change the window size to 4.

1_peaks-again-mcd.zip