Curve fitting, setting domain/forcing asymptote
14 Ansichten (letzte 30 Tage)
Ältere Kommentare anzeigen
Playing around with data analysis. I have no experience in this area so apologies if I'm asking obvious questions.
I have two data vectors that I want to find the relationship between.
I have with cftool found an exponential function that seems to describe it fairly well. But this function gives a bunch of values outside of my physically possible domain of x-values.
Is it possible to set conditions on the function fitting? For example, I know that y will tend to infinity as x approaches 1 from the right, and y will tend to 0 as x approaches infinity.
0 Kommentare
Akzeptierte Antwort
Tom Lane
am 17 Mai 2013
I can't think of a generic way to constrain a function to tend to infinity as x approaches 1, but you might have some luck defining a function that has that behavior and fitting it. For example:
load census % define some data having your shape
x = (cdate-1775)/10;
y = 1./pop;
ft = fittype('b1/((x-1)^b2)'); % has the desired asymptotic behavior
f = fit(x,y,ft,'start',[1 1])
plot(x,y,'bx', x,f(x),'r-') % not a great fit, but it's a start
0 Kommentare
Weitere Antworten (0)
Siehe auch
Kategorien
Mehr zu Get Started with Curve Fitting Toolbox finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!