Hi, I am sorry for this question, but I am trying to speed up an application.... I will need to fit many x-y data sets (input from text files) to 4-parameter Pseudo-Voigt peak function. Until now I used SigmaPlot macro to do it (enclosed just in case...)
peaksign(q) = if(total(q)>q[1], 1, -1) xatymin(q,r) = xatymax(q,max(r)-r) [Parameters] a = if(peaksign(y)>0, max(y), min(y)) ''Auto {{previous: 60.8286}} b = fwhm(x,abs(y))/2 ''Auto {{previous: 0.656637}} c = .5 ''Auto {{previous: 6.82973e-010}} x0 = if(peaksign(y)>0, xatymax(x,y), xatymin(x,y)) ''Auto {{previous: 3.19308}} [Equation] f = a*(c*(1/(1+((x-x0)/b)^2))+(1-c)*exp(-0.5*((x-x0)/b)^2)) fit f to y (manageable for ~100), but it looks like the next project would need to process ~1000 member sets. I am not as familiar with R to find the right info (although I can use R in general). I am also nearly sure that there should be a solution to this task "out there" ready to be modified... Could you be so kind and direct me please to the right package or web-site with examples? Thank you very much Dr. Petr Pancoska Department of Pathology SUNY Stony Brook, NY 11794 phone: (631)-444-3030 ****************************************************************************** This e- mail message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient, please contact the sender by e-mail and destroy all copies of the original. ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html