Hands-On Data Analysis with Pandas

Creating new data

First, we will cover adding new rows and columns, and later we will delete them. Creating new columns can be achieved in the same fashion as variable assignment. For example, we can create a column of ones for our data:

>>> df['ones'] = 1>>> df.head()

The new column is created to the right of the original columns, with a value of 1 for every row:

alert	mag	magType	place	time	title	tsunami	ones
0	NaN	1.35	ml	9km NE of Aguanga, CA	1539475168010	M 1.4 - 9km NE of Aguanga, CA	0	1
1	NaN	1.29	ml	9km NE of Aguanga, CA	1539475129610	M 1.3 - 9km NE of Aguanga, CA	0	1
2	NaN	3.42	ml	8km NE of Aguanga, CA	1539475062610	M 3.4 - 8km NE of Aguanga, CA	0	1
3	NaN	0.44	ml	9km NE of Aguanga, CA	1539474978070	M 0.4 - 9km NE of ...