#7 fit command issue
The following issue has been reported by email:
Hello Dominic,
Hope all is well.
I would appreciate if you could provide some assistance please with the following:
I have a function which I wish to fit to my data. I get the following error message which I don't understand. I tried to run the same commands in gnuplot but didn't encounter this error (I did have use log instead of ln in gnuplot to get ln)
pyxplot> height1=1634.66861345;center1=395.011265079;width1=15.8282972557;asym1=0.495963864298
pyxplot> height2=1606.61388466;center2=392.034035427;width2=11.3956998608;asym2=-0.278652616624
pyxplot> f(x) = height1*exp(-ln(2)*(ln(2.0*asym1*(x-center1)/width1+1)/asym1)**2) + height2*exp(-ln(2)*(ln(2.0*asym2*(x-center2)/width2+1)/asym2)**2)
pyxplot> fit f() "datafile.txt" u 1:2 via height1,height2,center1,center2,width1,width2,asym1,asym2
Error: The function log(x) is not defined at the requested point in parameter space.
Any ideas?
Thank you.
Regards,
Will.
