Pandas groupby object in legend on plot

Question

I am trying to plot a pandas groupby object using the code fil.groupby(\'imei\').plot(x=[\'time\'],y = [\'battery\'],ax=ax, title = str(i))

Th

Answer 1

Slightly tidied data:

    date         time             imei      battery_raw
0 2016-09-30 07:01:23  862117020146766       42208
1 2016-09-30 07:06:23  862117020146766        42213
2 2016-09-30 07:11:23  862117020146766        42151
3 2016-09-30 07:16:23 862117995146745       42263
4 2016-09-30 07:21:23  862117995146745       42293

Complete example code:

import matplotlib.pyplot as plt

fil = pd.read_csv('imei.csv', sep=r'\s*', engine='python')
fig, ax = plt.subplots(figsize=(18,6))

for name, group in fil.groupby('imei'):
    group.plot(x=pd.to_datetime(group['time']), y='battery_raw', ax=ax, label=name)

plt.show()

The x-values have to be converted to datetime for plotting to come out right, as usual. You could do that in the dataframe, too.

Result, labeled by imei:

(NOTE: edited to get rid of an oddity I tripped over the first time. If you pass a list as the y argument to group.plot, the list IDs will be used as the line labels, presumably as a handy default for when you're plotting several dependent variables at once.

#for name, group in fil.groupby('imei'):
#    group.plot(x=['time'], y=['battery_raw'], ax=ax, label=name)

)