[R] using lsoda() and nls() together
thpe at simecol.de
Wed May 27 00:06:26 CEST 2009
your problem is not really a problem of lsoda. The reason of the "crash"
is a violation of the statistical assumptions of least squares
regression due to dependency of residual variance on x. Due to this, K1
is varied over a very large range of values until numeric overflow occurs.
Note that you have an exponentially growing state, so log transformation
res <- nls(log(foo) ~
You may also consider using packages simecol (on CRAN) or FME (on
R-Forge) that both support constrained optimization of ode systems.
Hope it helps
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