Convolution of PET time-activity curve (TAC) with response function h(t) consisting of sum of three decaying exponential functions h(t) = a1*exp(-b1*t) + a2*exp(-b2*t) + a3*exp(-b3*t) Function integral from 0 to infinity is a1/b1 + a2/b2 + a3/b3. Output TAC, Co(t), is calculated from input TAC, Ci(t), as Co(T) = Ci(T) (x) h(T) , where (x) denotes the operation of convolution. To use sum of two exponentials as the response function, enter zeroes for a3 and b3. To use a mono-exponential, set a2 and b2 to zero, too. Usage: convexpf [Options] tacfile a1 b1 a2 b2 a3 b3 outputfile Options: -i=<Interval> Sample time interval in convolution; by default the shortest interval in the plasma data; too long interval as compared to b's leads to bias. -auc=1 Scale response function to have integral from 0 to infinity to unity; that will lead to similar AUC for the input and output TACs. -h0=1 Scale response function to h(0)=1. -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. The units of a's and b's must be compatible with units of the TAC, and the optional sample interval. For accurate results, input TAC should have very short sampling intervals. Frame durations are not used, even if available in the TAC file. Example: convexpf -auc=1 plasma.tac 1 0.05 0 0 0 0 simulated.tac See also: sim_3tcm, fit2dat, tacadd, simdisp, simframe, sim_av, convsurg Keywords: TAC, simulation, modelling, convolution

This program comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome

to redistribute it under GNU General Public License.

Source codes are available in https://gitlab.utu.fi/vesoik/tpcclib.git.