How do I get the number of rows of a pandas dataframe df?

For a dataframe df, one can use any of the following:

• len(df.index)
• df.shape[0]
• df[df.columns[0]].count() (== number of non-NaN values in first column)

Code to reproduce the plot:

import numpy as np
import pandas as pd
import perfplot
perfplot.save(
“out.png”,
setup=lambda n: pd.DataFrame(np.arange(n * 3).reshape(n, 3)),
n_range=[2**k for k in range(25)],
kernels=[
lambda df: len(df.index),
lambda df: df.shape[0],
lambda df: df[df.columns[0]].count(),
],
labels=[“len(df.index)”, “df.shape[0]”, “df[df.columns[0]].count()”],
xlabel=“Number of rows”,
)