cftool and log-scale

Hey i want to use curve fitting with log-scale y-axes, but it seems i cant change the y-axes from linear to log in cftool. i must have the figure in log-y-axes before fitting because i need to exclude some part of it.

I try the metod with genrate code, and replace plot with semilogx, it only works after the fitting....

basiclly i want to: log-Y-axes -> exclude some parts -> and do linear fitting with the rest. any idea???

[Geoff]

It's not really 'linear' fitting if your data has a logarithmic trend. Either scale your Y-data by log, then do your exclusions and linear fitting, or do a logarithmic fit (which appears to be linear on a log scale)