No closed solution known for linexp, we use a Newton approximation.
Arguments
- x
Result of a nlme fit, with named components `tempt, beta, logbeta,
kappa, logkappa` depending on model. Function used `logbeta` when it is present,
in `x`, otherwise beta, and similar for logkappa/kappa.
Value
Half-emptying time. Name of evaluated function is returned as
attribute fun. Negative of slope is returned as attribute slope.