meaning of "%" in printing the result of adfuller in Python

Question

There's a % in the following code, which is from ARIMA Model in Python .

from statsmodels.tsa.stattools import adfuller
from numpy import log

result = adfuller(df.value.dropna())
print('ADF Statistic: %f' % result[0]) 
print('p-value: %f' % result[1])

I'm confused to what the % does in the print statement (last line). What does it do to the result? Or, does it represent mod?

Thanks!

Answer 1

The % symbol is related to string interpolation rather then the print. It is a way to format string. You can read here more about it.

It is just one of many ways to format strings in python:

1. “Old Style” String Formatting (% Operator)
2. “New Style” String Formatting (str.format)
3. String Interpolation / f-Strings (Python 3.6+)
4. Template Strings (Standard Library)