Community request time! Thanks to Leonah for the tutorial request about how to multiply columns in pandas
Multiplying columns together is a foundational skill in Pandas and a great one to master. Good thing it is straightforward and easy to pick up.
1. df['your_new_column'] = df['col1'] * df['col2']
In the video below we’ll review two methods for multiplying columns together and saving the result on your dataframe.
Code from the video. Looks like the formatting of many columns is very off. To view a nice version, head over to the git hub link below.
Mulitplying columns together to make a 3rd column¶
Goal: Multiply columns
In [1]:
import pandas as pd
In [2]:
df = pd.read_csv('../data/Street_Tree_List.csv')
In [4]:
df.head(2)
Out[4]:
Method 1: Multiply Series together¶
In [9]:
df['multiplied_column'] = df['TreeID'] * df['SiteOrder']
Method 2: Iterate through column and multiply¶
In [20]:
results_list = []
for i, row in df.iterrows():
result = (row['TreeID']/2) * row['SiteOrder']
results_list.append(result)
In [22]:
df['multiplied_column2'] = results_list
In [23]:
df.head(3)
Out[23]:
In [ ]:
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