// Script to calculate the time integral for a single synaptic event given
// tau1, tau2, and gmax.
function calc_syn_integ(gmax, tau1, tau2)
float gmax, tau1, tau2
float pktime = ({log {tau1}}-{log {tau2}})*{tau1}*{tau2}/({tau1}-{tau2})
float pkval = ({gmax} / ({tau1} - {tau2})) \
* ({exp {-{pktime} / {tau1}}} - {exp {-{pktime} / {tau2}}})
float A = gmax/{abs {pkval}}
// Now have all components of synapse alpha function:
// gsyn = ((A * gmax)/(tau1-tau2)) * (exp(-t/tau1) - exp(-t/tau2))
// Can now integrate alpha function over time. Stop integration when
// time reaches 5*tau2, where amplitude < 1% of peak.
float syninteg = ({A} * {gmax}) / ({tau1} - {tau2}) \
* (({tau2} * {exp -5}) - ({tau1} * {exp {-5*{tau2}/{tau1}}}) \
- {tau2} + {tau1})
return {syninteg}
echo
echo synInteg is {syninteg}
echo
end
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