Wrangling -- Intro to pandas.DataFrames.ipynb

Kernel: Python 3

# same ol boilerplate, except no csv.DictReader
from os import makedirs
from os.path import join

%matplotlib inline
import matplotlib.pyplot as plt
# but now we got some pandas
import pandas as pd

DATA_FILENAME = join('data', 'climate', 'extracted', 'nasa-ghgases-co2-mean.csv')

df = pd.read_csv(DATA_FILENAME)

df.head(10)

Subsetting columns with the iloc attribute

iloc provides a way to slice a range of rows of a dataframe. Note the indexes are preserved:

df.iloc[5:10]

Select columns

Just pass in a list of column names

df[['co2_ppm_mean', 'year']].head()

Adding a derived column

Add a decade column

df['decade'] = df.round({'year': -1})['year']
df.head()

Add change over year for the co2_ppm_mean

Grouping