Plotting Different Groups with Plotly

问题

I have a dataframe in python that looks a bit like this:

Device   Date      Reading
Device1  1/02/17   100.33
Device1  2/02/17   300.23
Device1  3/02/17   99.00
Device2  1/02/17   11.24
Device2  2/02/17   654.00
Device2  3/02/17   4543.4
Device3  1/02/17   3243.5
Device3  2/02/17   545.43
Device3  3/02/17   4545.0

It basically has devices, dates and a reading. It's much larger than the snippet I've given.

I am trying to plot, preferably using plotly because it is is interactive and allows me to zoom, etc, which is ideal for this type of dataset.

I want to plot the date on the X axis, reading on the Y axis, and have individual lines (which are different coloured) for each device with a legend. However, everything is in one data frame and I don't want to manually add traces, which would take ages because of the size of my dataset.

I have searched high and low for a solution and nothing seems to work. I have tried the plotly site, cufflinks, but it seems quite complex and there's little info online (for cufflinks). In R, I would do something like colour=device to signify that I want different it to be sorted by device, but I can't seem to work it out in Python.

Could anybody advise (remember everything is in one data frame)?

回答1:

I found out that using pd.groupby method is a pretty convenient way to generate traces in loops.

import pandas as pd
import plotly.graph_objs as go
from plotly.offline import iplot, init_notebook_mode

init_notebook_mode()

# Copy OP's example and load from clipboard
df = pd.read_clipboard()

grouped = df.groupby('Device')
data = [go.Trace(dict(x=values['Date'], y=values['Reading'], name=key,
                       mode='line')) for key, values in grouped]
iplot(data)

You may also set the color you want by defining beforehand a dict of device: color, for example.

来源：https://stackoverflow.com/questions/43941933/plotting-different-groups-with-plotly