## fit_dexp - tpcclib 0.7.3 © 2019 by Turku PET Centre

Non-linear fitting of the sum of 1-5 exponential functions to decaying
time-activity curve (TAC).
Function:
f(x) = a1*exp(k1*x) + a2*exp(k2*x) + a3*exp(k3*x) + ...
, where a's > 0 and k's < 0.
Usage: fit_dexp [Options] tacfile parfile
Options:
-5 | -4 | -3 | -2 | -1
Fit to sum of specified number of exponential functions; by default
determined 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.
-svg=<Filename>
Fitted and measured TACs are plotted in specified SVG file.
-nr=<value>
Number of basis functions, used in determination of initial parameter
estimates and number of exponentials for nonlinear fitting;
default is 100.
-peak | -peak1
Fit is started only at the TAC peak, or at the next sample after peak.
-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.
If TAC file contains more than one TAC, only the first is used.
Function parameters are written in fit format.
See also: fit_exp, fit_fexp, fit_ratf, fit2dat, extrapol, paucinf, tacln
Keywords: TAC, curve fitting, extrapolation