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## Gaussian fit

version 1.5.0.0 (2.15 KB) by Przemyslaw Baranski

### Przemyslaw Baranski (view profile)

Fits Gaussian curve into points. The curve is understood as a probability density function, pdf.

Updated 23 Feb 2012

The function fits Guassian probability density function into a set of points. Standard deviation and mean are returned.

R

VoyageR

VoyageR

### VoyageR (view profile)

Data is not normalized! The pdf sums to: 0.000000. Normalizing...

Undefined function 'exp' for input
arguments of type 'uint8'.

Error in gaussfit (line 89)
dfdsigma =
-1/(sqrt(2*pi)*sigma^2)*exp(-((x-mu).^2)
/ (2*sigma^2));

How to normalize my data ?

John TB

### John TB (view profile)

Good and helpful routine for 1D Gaussian fitting!

any

### any (view profile)

Hi,I have a problem with this program...Data is not normalized! The pdf sums to: 0.454068. Normalizing...
What is the problem???
Thank you...

Georges

sr

### sr (view profile)

My data has a constant (with some spread) y-offset. Please let me know what to do in your code to make it fit? Thanks

sr

### sr (view profile)

My data has a constant (with some spread) y-offset. Please let me know what to do in your code to make it fit? Thanks

Eddie

Thijs

### Thijs (view profile)

Updating my previous comment for future readers.

The problem was indeed incorrectly scaled data. The function works quite beautifully now.

Przemyslaw Baranski

### Przemyslaw Baranski (view profile)

Hi Thijs. Is your data properly scaled? I mean a probability density function should sum up to 1 and so should roughly the histogram for which your try to fit the curve

Thijs

### Thijs (view profile)

I changed the line 88 from exit to return.

The function works rather poorly on my data though, I get better results minimizing the logarithmic residuals.

 23 Feb 2012 1.5.0.0 Checking if the input points (x,y) are sorted. If not sort them. Improved checking if p.d.f sums up to 1 23 Feb 2012 1.4.0.0 Normalization of data. Added some infos to the helpd section 19 Feb 2012 1.1.0.0 More description, so that it can perhaps be easier found
##### MATLAB Release Compatibility
Created with R2007b
Compatible with any release
##### Platform Compatibility
Windows macOS Linux