


How do you access DataFrame columns and rows as lists in Python\'s Pandas library?
Accessing DataFrame Columns and Rows as Lists
In Python's Pandas library, a DataFrame contains rows and columns of tabular data. To access the contents of a DataFrame column or row, you can use the following methods:
1. Getting Column Contents
To retrieve the contents of a DataFrame column as a list, use the tolist() method on the Series object representing the column. You can also cast the Series to a list using the list() function.
<code class="python">import pandas as pd # Create a DataFrame from sample data df = pd.DataFrame({ 'cluster': ['A', 'A', 'A', 'B', 'B', 'B', 'C', 'C', 'C'], 'load_date': ['1/1/2014', '2/1/2014', '3/1/2014', '4/1/2014', '4/1/2014', '4/1/2014', '7/1/2014', '8/1/2014', '9/1/2014'], 'budget': [1000, 12000, 36000, 15000, 12000, 90000, 22000, 30000, 53000], 'actual': [4000, 10000, 2000, 10000, 11500, 11000, 18000, 28960, 51200], 'fixed_price': ['Y', 'Y', 'Y', 'N', 'N', 'N', 'N', 'N', 'N'] }) # Convert column values to a list cluster_list = df['cluster'].tolist() # Alternatively, you can cast the Series to a list cluster_list = list(df['cluster'])</code>
2. Getting Row Contents
To obtain the contents of a DataFrame row as a list, use the loc or iloc accessor with the appropriate row index.
<code class="python"># Get row 1 as a list using 'loc' row_1_list = df.loc[0].tolist() # Get row 1 as a list using 'iloc' row_1_list = df.iloc[0].tolist()</code>
Sample Output:
cluster_list: ['A', 'A', 'A', 'B', 'B', 'B', 'C', 'C', 'C'] row_1_list: [1000, 4000, 'Y']
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