pandas DatetimeIndex to matplotlib x-ticks - python-3.x

Question

I have a pandas Dateframe with a date index looking like this:
Date
2020-09-03
2020-09-04
2020-09-07
2020-09-08
The dates are missing a few entries, since its only data for weekdays.
The thing I want to do is: Plot the figure and set an x tick on every Monday of the week.
So far I've tried:
date_form = DateFormatter("%d. %b %Y")
ax4.xaxis.set_major_formatter(date_form)
ax4.xaxis.set_major_locator(mdates.WeekdayLocator(byweekday=MO))
But it will start with 1970 and not with the actual date index.
Then I tried to:
mdates.set_epoch('First day of my data')
But this won't help since Saturday and Sunday is skipped in my original Index.
Any ideas what I could do?

Answer 1

If you draw a line plot with one axis of datetime type,
the most natural solution is to use plot_date.
I created an example DataFrame like below:
Amount
Date
2020-08-24 210
2020-08-25 220
2020-08-26 240
2020-08-27 215
2020-08-28 243
...
Date (the index) is of datetime type.
The code to draw is:
import matplotlib.pyplot as plt
import matplotlib.dates as mdates
fig, ax = plt.subplots()
plt.xticks(rotation=30)
ax.plot_date(df.index, df.Amount, linestyle='solid')
ax.xaxis.set_major_locator(mdates.WeekdayLocator(byweekday=0))
plt.grid()
plt.show()
The picture I got is:
As you can see, there is absolutely no problem with x ticks and they
are just on Mondays, as you want.