Pandas plot dual axis using only numerical values

Question

I have dataframe like this,

import pandas as pd
from matplotlib import pyplot as plt

data = {
    "TIMEFRAME": ["9/12/2014 17:52", "10/12/2014 5:02", "10/12/2014  8:04"],
    "Volumetric Flow Meter 1": [0.82, 0.88, 0.9],
    "Pump Speed (RPM)": [2.5, 2.7, 3.01],
    "Data Source": ["raw data", "raw data", "raw data"],
    "PUMP FAILURE (1 or 0)": [0, 0, 1],
}
df = pd.DataFrame(data)

df

TIMEFRAME       Volumetric Flow Meter 1  Pump Speed (RPM)  Data Source   PUMP FAILURE (1 or 0)
9/12/2014  17:52           0.82                   2.5      raw data           0   
10/12/2014 5:02            0.88                   2.7      raw data           0
10/12/2014 8:04            0.90                   3.01     raw data           1

I am trying to loop through the dataset, plotting every numerical variable individually, against the Pump Failure to identify the trends. I have to create a list of every numerical columns in the dataframe and loop through it to plot them against the PUMP FAILURE (1 or 0) column.

For each plot, I have to ensure that I have a dual axis set up so I can see the Pump Failure (0 or 1) on the second Y-axis, and the attribute on the first Y-Axis.

The output is something like this,

Given code,

ListOfVariables=[df["Pump Speed (RPM)"],df["Volumetric Flow Meter 1"]]

for item in ListOfVariables:
    first_axis = df[''].plot #Looping through every item in the dataframe
    second_axis = first_axis.twinx() #The Twinx function is used to ensure we share the X-Axis for both plots
    second_axis.plot(df['PUMP FAILURE (1 or 0)'], color='teal')
    plt.title(item)
    plt.show()

I am confused about this part, first_axis = df[''].plot Not sure what to use.

Answer 1

Replace:

• ListOfVariables=[df["Pump Speed (RPM)"],df["Volumetric Flow Meter 1"]] with ListOfVariables=["Pump Speed (RPM)","Volumetric Flow Meter 1"]
• first_axis = df[''].plot with first_axis = df[item].plot()

And your code works: