Re: [Matplotlib-users] subclassing AutoDateFormatter correctly

[C M <cmp...@gm...>]

On Sun, Nov 28, 2010 at 8:52 PM, C M <cmp...@gm...> wrote:

> How can I correctly subclass AutoDateFormatter and use it in my code?
>
> What I am doing is copying the code from matplotlib's AutoDateFormatter and
> changing the strings for how the dates are represented and making that a
> class, MyAutoDateFormatter.  AutoDateFormatter expects a locator, and I
> think (?) the default is AutoDateLocator.  So in my code I am doing this:
>
>         adl = AutoDateLocator()
>         myformatter = MyAutoDateFormatter(adl)
>         axis.xaxis.set_major_formatter(myformatter)
>
> But when I run it, no matter the level of zoom, it says "2010" (when it
> should change depending on zoom level).
>
> However, if I go into the matplotlib dates.py code itself and save the same
> changes to the date strings there, and I comment out the above code, then it
> works:  the date strings change depending on level of zoom.
>

I've also just noticed that if I use the above code after the lines have
been plotted, but then I click on one of the points (which causes a
point-picking routine that ultimately plots a highlighting marker over that
point), the x axis suddenly changes to use MyAutoDateFormatter's format
strings.  (If I call it before I plot anything, it doesn't help, though).

Is the act of plotting somehow "refreshing" things?  What can I call in
order to force this to happen without actually plotting any additional
points after my lines are plotted?

Thanks,
Che