fit_exp - tpcclib 0.8.0 © 2023 by Turku PET Centre

Non-linear fitting of the sum of 1-3 exponential functions to PET plasma and
tissue time-activity curves (TACs).
 
Function:
 
  f(x) = p1*exp(p2*x) + p3*exp(p4*x) + p5*exp(p6*x)
 
Usage: fit_exp [Options] tacfile fitfile
 
Options:
 -3[e] | -2[e] | -1[e]
     Fit to sum of three (default), two, or single exponential function.
 -nonneg
     p1, p3 and p5 are constrained to values >= 0.
 -expneg
     p2, p4 and p6 are constrained to values <= 0.
 -starttime=<<Time (min)>|Peak>
     Set the sample time from where fitting is started (0 by default),
     or 'peak' to start fitting from common peak time.
 -endtime=<Time (min)>
     Set the sample time where fitting is stopped (last sample by default).
 -svg=<Filename>
     Fitted and measured TACs are plotted in specified SVG file.
 -autoname
     Names for fit file and fitted TAC file are set automatically
 -w1
     All weights are set to 1.0 (no weighting); by default, weights in
     data file are used, if available.
 -wf
     Weight by sampling interval.
 -h, --help
     Display usage information on standard output and exit.
 -v, --version
     Display version and compile information on standard output and exit.
 -d[n], --debug[=n], --verbose[=n]
     Set the level (n) of debugging messages and listings.
 -q, --quiet
     Suppress displaying normal results on standard output.
 -s, --silent
     Suppress displaying anything except errors.
 
Function parameters are written in fit (2) or result (3) format,
depending on filename extension (.fit or .res).
 
References:
1. http://www.turkupetcentre.net/petanalysis/doc/format_tpc_dft.html
2. http://www.turkupetcentre.net/petanalysis/doc/format_tpc_fit.html
3. http://www.turkupetcentre.net/petanalysis/doc/format_tpc_res.html
 
See also: fit_fexp, fit_dexp, llsqe3, fit_ratf, fit2dat, extrapol, tacln
 
Keywords: TAC, curve fitting, input, simulation, extrapolation