[R] Help with modFit of FME package

[Paola Lecca]

Dear R users,

I'm trying to fit a set an ODE to an experimental time series. In the attachment you find the R code I wrote using modFit and modCost of FME package and the file of the time series.

When I run summary(Fit) I obtain this error message, and the values of the parameters are equal to the initial guesses I gave  to them.

The problem is not due to the fact that I have only one equation (I tried also with more equations, but I still obtain this error).

I would appreciate if someone could help me in understanding the reason of the error and in fixing it.

Thanks for your attention,
Paola Lecca.

Here the error:

> summary(Fit)

Parameters:
              Estimate Std. Error t value Pr(>|t|)
pro1_strength        1         NA      NA       NA

Residual standard error: 2.124 on 10 degrees of freedom
Error in cov2cor(x$cov.unscaled) : 'V' is not a square numeric matrix
In addition: Warning message:
In summary.modFit(Fit) : Cannot estimate covariance; system is singular



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