Get current group name in a Pandas data frame plot

June 22, 2022

I have a data frame like that (it’s just the head) :

                       Timestamp Function_code  Node_id  Delta
0     2000-01-01 10:39:51.790683      Tx_PDO_2       54  551.0
1     2000-01-01 10:39:51.791650      Tx_PDO_2       54  601.0
2     2000-01-01 10:39:51.792564      Tx_PDO_3       54  545.0
3     2000-01-01 10:39:51.793511      Tx_PDO_3       54  564.0

There are only two types of Function_code : Tx_PDO_2 and Tx_PDO_3

I plot in two windows, a graph with Timestamp on the x-axis and Delta on the y-axis. One for Tx_PDO_2 and the other for Tx_PDO_3 :

delta_rx_tx_df.groupby("Function_code").plot(x="Timestamp", y="Delta", )

Now, I want to know which window corresponds to which Function_code

I tried to use title=delta_rx_tx_df.groupby("Function_code").groups but it did not work.

>Solution :

There may be a better way, but for starters, you can assign the titles to the plots after they are created:

plots = delta_rx_tx_df.groupby("Function_code").plot(x="Timestamp", y="Delta")
plots.reset_index()\
     .apply(lambda x: x[0].set_title(x['Function_code']), axis=1)