File Exchange

image thumbnail

Lognormal Helpers

version 1.0 (4.43 KB) by

Fitting for lognormal distributions



View License

Contains fitting for histogram data on normal and lognormal distributions. Though still requiring the fitting toolbox, the parameters are adapted in such a way that Matlab can actually fit the values (e.g. very small x values)!

Functions return mu and sigma parameter, scaling factor (for non-unit distributions) and goodness of fit.
Additionally included are logn2mean and mean2logn to convert between logn parameters mu/sigma and mean/std value (in contrast to lognstat which returns mean and variance)

Comments and Ratings (2)

John Adcox

Nevermind....sorry :-(. I was thinking variance, you are outputting standard deviation. My mistake

John Adcox

I think there might be some math errors in your logn2mean and mean2logn scripts. They do not match up with Matlab's lognstat functions.

I think you need to change line 15 in logn2mean to:
s = exp(2*mu + sigma.^2) .* (exp(sigma.^2) - 1);

And line 14 in mean2logn to:
sigma = sqrt(log(s./m.^2 + 1));

This would then follow the equations laid out my the Mathworks website located at:

MATLAB Release
MATLAB 7.14 (R2012a)

Download apps, toolboxes, and other File Exchange content using Add-On Explorer in MATLAB.

» Watch video

Win prizes and improve your MATLAB skills

Play today