### Highlights from Find Peak Value

4.22222
4.2 | 27 ratings Rate this file 69 Downloads (last 30 days) File Size: 40 KB File ID: #4242

# Find Peak Value

by

### Geng Jun (view profile)

10 Dec 2003 (Updated )

### Editor's Notes:

This file was a File Exchange Pick of the Week

File Information
Description

It's a simple function. Can help you find peak value from a lot of datas. It contains some demos.

It's my first time to submit file, thanks for your using.

MATLAB release MATLAB 6.5 (R13)
27 Jun 2014 haier

### haier (view profile)

05 Jul 2012 Tharindu

### Tharindu (view profile)

Try this one;
http://www.mathworks.com/help/toolbox/signal/ref/findpeaks.html

Comment only
07 Jun 2012 Tharindu

### Tharindu (view profile)

Thanks, It works great!

27 Apr 2012 Jesse Sipple

### Jesse Sipple (view profile)

Has anyone had any trouble finding the peaks for a vector that has both positive and negative values? Does not seem to be working with that.

Comment only
29 Jun 2011 Kami

### Kami (view profile)

Range is a 4-element vector:
[Xmin, Xmax, Ymin, Ymax]
Xmin: the lower x boundary of region of interest(ROI).
Xmax: the upper x boundary of ROI
Ymin and Ymax are the same as Xmin and Xmax.
For example,
t=fpeak(A,B,30,[23,90,700,inf]);
means:
find the peaks whose x are between 23 and 90 and their values is between 700 and inf.

Comment only
29 Jun 2011 Kami

### Kami (view profile)

I would be grateful if you put some explanation about the inputs. What is the input "Range"? and why is it a four-element vector?

Comment only
02 Feb 2011 Caleb

### Caleb (view profile)

Great performance.

27 Sep 2010 Alex

### Alex (view profile)

Ah never mind... d'oh

Comment only
27 Sep 2010 Alex

### Alex (view profile)

Sorry if this is a dumb question, but where is this getPeak function that is called within this function?? I tried finding it on File Exchange and am not getting anything...

Thanks

Comment only
30 Aug 2010 JQZhou

### JQZhou (view profile)

There is a bug in this program. when the peak/valley contains more than 1 point with same value, this program will just ignore this peak/valley.

correction:
replace
tP=(sum(y(top:bottom)>=y(i))==1);
bP=(sum(y(top:bottom)<=y(i))==1);
with
tP=(y(ii)==max(y(top:bottom)));
bP=(y(ii)==min(y(top:bottom)));

Comment only
27 May 2010 David Jessop

### David Jessop (view profile)

Poorly explained, poor performance for large data sets and requires too much parameter tweaking in order to find peaks.

19 Apr 2010 antonio Acampora

### antonio Acampora (view profile)

12 Aug 2009 john Chandler

### john Chandler (view profile)

it doesn't work.

Change line 9 in ma.m to
t=fpeak(A,B,30,[0,90,100,inf]);

and you will see that it picks peaks and valleys, both.

27 Aug 2008 shilin guo

working perfect!!

21 Jul 2008 Kristin Golmon

Doesn't work when there are two data matching values at the top of a peak. Other than that, perfect.

10 Jun 2008 Vinh Nguyen Quang
05 Jun 2008 Rishi Bansal

works like a charm!!!

Excellent! Thank you

09 Feb 2008 Estella Liu

This works great!! Thank you so much :)

11 Dec 2007 Mukesh V.

this is the best that I found, relavent code

21 Apr 2007 Sunil Arya

I found a very good m code to pick up the peak data.
Thankyou

06 Mar 2007 Rory Gamble

I would really like to see a version of this that does functions of two wariables, eg extreme.m/extreme2.m

Comment only
15 Dec 2006 Linda Best

i found extreme.m is geat and also find peaks from surface: extreme2.m! But this was the first i used

20 Jun 2006 Frederick Lu

Performance need improvements.

31 Aug 2005 Bernard Grundlehner

Too slow on large sets of data. I prefer peakdetect.m

22 Feb 2005 Alexandre Chirokov

I added small code (see below) to the getPeak function, now it works even better on my data.

if abs(y(i)-avg)<delta
p=[nan,nan];
return;
end
delta = std(y)
avg = mean(y) it can be local std and mean with window equal to +-several values of "s"

02 Feb 2005 ling lin

It saved my time.

23 Nov 2004 Geng Jun

Comment only
28 Jul 2004 Tom Wang

Not sure if I'm using this correctly but I'm not getting accurate peaks at all. My call to the function is fpeak(1:129, data, 2). "data" has 129 values. I'm getting values of 4.0 0 next to 5.0 1, and 3.0 2. Any suggestions would be appreciated.

Comment only
20 Jul 2004 Peng Wang

I just need a function to find peaks. Thank you so much to solve my problem and save my time. It works great. The sensitivity is actually the half-width of the peak. A point is defined as a peak if its value is biger than that of any s points ahead and s points behind.

21 Jun 2004 James McDonald

It worked perfectly for my example. Thanks!!

03 Jun 2004 Ertu sariaslan

Thanks for solving my Problem !!!
But I dont understand the sensitivity, can anybody help me ???

18 Apr 2004 Keven Chang

Great Job.

06 Apr 2004 Barney de Villiers

Really Good!
Thanks, It helps me alot!

12 Dec 2003 ma alex

GOOD!

12 Dec 2003 Jiao Shibo

You are Genius!

12 Dec 2003 gu wan

very good