Re: Omitting values for Leasqr

[Francesco Potortì]

>I am trying to fit an exponential curve to data using the leasqr() function.
>I can fit the data no problem. However my data has a lot of noise and our
>policy is to remove data points that are outside of 2 standard deviations of
>the mean of the residuals from an exponential curve that is initially fit to
>the data. I have tried replacing the values with NA or NaN and it exits with
>an error of "CONVERGENCE NOT ACHIEVED!" my temporary solution is to replace
>the value with a local mean, however ideally I would like to omit the value
>without changing the data.

The leasqr function has the possibility of specifying weights for each
data point. You just set weight 1 to everything but the data you want to
ignore, whose weight you set to a low value.

Or you just create a new vector without the offending data points and do
the fitting on that one.

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