On Sunday 27 August 2006 22:09, Eric Firing wrote: > Darren Dale wrote: > > A while back, I put some effort into rendering an offset ticklabel, which > > allowed the user to do something like > > > > plot(linspace(100000100, 100000200, 100)) > > > > and the plot would look like a plot from 0 to 100, with a "+100000100" > > rendered in a new label near the far end of the axis. This doesnt work > > quite as well as it used to, because the axes autoscaling is setting the > > plot range to something like the average plus and minus 6%. I have tried > > tracing the source of this change, but I can't find it. It might be > > buried in the _transforms extension code, and I've never been able to > > wrap my head around mpl's transforms. > > > > Does anyone know why autoscaling is defaulting to this +-6% range? Does > > it have to be this way? I'm trying to improve the scalar formatter > > (supporting engineering notation, cleaning up the code). > > Yes. It is not a +-6% range in general, rather it is an adjustment that > is made if the range is very small. The relevant method in Locator is: > > def nonsingular(self, vmin, vmax, expander=0.001, tiny=1e-6): > if vmax < vmin: > vmin, vmax = vmax, vmin > if vmax - vmin <= max(abs(vmin), abs(vmax)) * tiny: > if vmin==0.0: > vmin -= 1 > vmax += 1 > else: > vmin -= expander*abs(vmin) > vmax += expander*abs(vmax) > return vmin, vmax > > I know I did it this way for a reason, but I don't remember exactly what > it was--whether it was because of problems with zooming when the zoom > range gets too small (this was definitely a big problem), or because of > problems with the rest of the locator code, or because it seemed to me > to be roughly the desired behavior in most cases. Maybe it was all of > the above. Certainly, something like this is needed--I think you will > find that things go bad rapidly if vmin gets too close to vmax. I put > in the "expander" and "tiny" kwargs in case of future need, but only > expander is non-default (e.g., 0.05) in other parts of ticker.py, and > neither kwarg is presently exposed to the user. That could be changed.
I don't understand, I spent a lot of time making the scalarformatter work with precisely this scenario (zooming in on extremely small ranges), and it was working very well. I don't know of any circumstance where there was a problem, maybe you could be more specific about the big problems you encountered. Darren ------------------------------------------------------------------------- Using Tomcat but need to do more? Need to support web services, security? Get stuff done quickly with pre-integrated technology to make your job easier Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 _______________________________________________ Matplotlib-devel mailing list Matplotlib-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/matplotlib-devel
