Re: [Gnuplot-info] ROC curves in GNUPLOT

[Thomas S. <t.s...@fz...>]

you have two points fixed (the end points) and one free point,
so you may fit one parameter only.

the function could be
f(x)=(x/100.)**a *100.
but you need to set 'a' to a reasonable value if the fit
doesn't converge directly.

a=7
fit f(x) 'datafile' via a

gives

Final set of parameters 
======================= 

a               = 7.21257


nirud wrote:
> 
> Hi. I'm trying to get ROC curves in gnuplot. If somebody doesn't know what
> kind of ROC curves - it's easy to explain what I want to have
> 
> example:
> xrange - 0:100
> yrange - 0:100
> 
> I have 3 points (0,0), (100, 100) and (80,20) what I want it's to connect
> this point whith curves not lines. I tried to use function fit (with
> a*exp(X*b), a*log(x*b) or even a*x**3 + b) but it doesn't works... I know
> that as more point I have that easier I can plot my curves, but
> unfortunately I can have only this 3 points.
> 
> Maybe here is anybody who can help me with that problem and know something
> what can put me on the right track... Txh in adnance
> 
> PS: sorry for my ENG mistakes...
> 

-- 
View this message in context: http://www.nabble.com/ROC-curves-in-GNUPLOT-tp20879557p20926044.html
Sent from the Gnuplot - User mailing list archive at Nabble.com.