Hello,
Function sddspfit seems to return incorrect result of fitting in some cases. Works well for polynomial orders 0,1,2 - but gives constant offset when I add orders of 3 and higher.
The example of data file and script attached (SL6 and SL7 were used)
Thank you!
Ksenia, BINP
sddspfit for high orders
Moderators: michael_borland, soliday
sddspfit for high orders
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Re: sddspfit for high orders
Ksenia,
The problem is that the independent quantity (H6) has a large average value compared to its range. This causes numerical precision problems. You can fix this by adding the -autoOffset option, but should realize that the meaning of the fit coefficients is then changed.
--Michael
The problem is that the independent quantity (H6) has a large average value compared to its range. This causes numerical precision problems. You can fix this by adding the -autoOffset option, but should realize that the meaning of the fit coefficients is then changed.
--Michael