PR Summary

Ifdates.AutoTickLocator was on the YEARLY frequency, it didn't respect theinterval_multiples kwarg. This changes that by using the YearlyLocator ifinterval_multiples=True

(Of course I still think dateticks should be overhauled, but thats a bigger project)

Fixes#9838

importdatetimeimportmatplotlib.datesasmdatesimportmatplotlib.pyplotaspltimportnumpyasnpx= [datetime.datetime(1966,1,1),datetime.datetime(2017,1,1)]ticks= [datetime.datetime(i,1,1)foriinrange(1970,2020,10)]y=np.arange(len(x))fig,ax=plt.subplots()ax.plot_date(x,y)locator=mdates.AutoDateLocator(interval_multiples=True)ax.xaxis.set_major_locator(locator)plt.show()

PR Checklist

• Has Pytest style unit tests
• Code is PEP 8 compliant
• New features are documented, with examples if plot related
• Documentation is sphinx and numpydoc compliant