python - Matplotlib date manipulation so that the year tick show up every 12 months

Question

I'm plotting a figure where the default format shows up as:

I would like to modify it so that the month ticks show up every 1 month but keep the year. My current attempt is this:

years = mdates.YearLocator()
months = mdates.MonthLocator()
monthsFmt = mdates.DateFormatter('%b-%y')
dts = s.index.to_pydatetime()

fig = plt.figure(); ax = fig.add_subplot(111)
ax.plot(dts, s)
ax.xaxis.set_major_locator(months)
ax.xaxis.set_major_formatter(monthsFmt)

but it's not producing the right result:

How exactly do I need to modify it so that it shows up like the first but with the months ticks appear every month?

Answer 1

Figured out one solution, which is to stick months into the minor ticks and keep years as the major.

E.g.

years = mdates.YearLocator()
months = mdates.MonthLocator()
monthsFmt = mdates.DateFormatter('%b') 
yearsFmt = mdates.DateFormatter('

%Y')  # add some space for the year label
dts = s.index.to_pydatetime()

fig = plt.figure(); ax = fig.add_subplot(111)
ax.plot(dts, s)
ax.xaxis.set_minor_locator(months)
ax.xaxis.set_minor_formatter(monthsFmt)
plt.setp(ax.xaxis.get_minorticklabels(), rotation=90)
ax.xaxis.set_major_locator(years)
ax.xaxis.set_major_formatter(yearsFmt)

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