Steve, You can't display zero or negative numbers on a log chart.
I'd suggest you filter the equity array before displaying, setting some minimum value for all values that are less than that. You might need to use trial and error to pick a good minimum value that will display the rest of your data in a useful fashion. You won't then be able to see values below that minimum, but the rest of your data should make more sense. GP --- In [email protected], "Steve Dugas" <[EMAIL PROTECTED]> wrote: > > Hi All, > > I wrote some code that plots an equity line with overlying regression line. It will plot correctly on linear or semi-log chart. Then I applied a little change so that the scale on the right starts at zero and displays % return rather than actual account equity. The line looks the same, only the scale is different. I like this better, except that the line looks very strange when I switch to the logaritmic chart. I *think* this is because the line starts at zero, and may go negative at times, and logarithms do not seem to work so well with these values. Just wondering if any math wizards out there might know of a workaround to correct this kind of problem? Thanks very much! > > Steve >
