Q.Can you write a program to count the number of rows and columns in a DataFrame?
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Start your 14-day free trial to unlock the full solution →Use the .shape attribute of a DataFrame to get a tuple (rows, columns), or use len(df) for rows and len(df.columns) for columns separately.
This is a code / query task — the question asks for a program that counts rows and columns in a DataFrame. The core idea is that a DataFrame in pandas has a built-in attribute .shape that returns exactly this information as a tuple. This is the most direct and Pythonic way to get both dimensions at once.
The .shape attribute is a property, not a method — so no parentheses are needed. It returns (number_of_rows, number_of_columns). If you need the values separately, you can unpack them into two variables.
Here's the complete, runnable solution:
import pandas as pd
# Sample DataFrame (you can replace this with any DataFrame)
data = {
'Name': ['Alice', 'Bob', 'Charlie', 'Diana'],
'Age': [25, 30, 35, 28],
'City': ['New York', 'London', 'Paris', 'Tokyo']
}
df = pd.DataFrame(data)
# Method 1: Using .shape (returns a tuple)
rows, cols = df.shape
print(f"Number of rows: {rows}")
print(f"Number of columns: {cols}")
# Method 2: Using len() for rows and .columns for columns
print(f"Rows (using len): {len(df)}")
print(f"Columns (using len(df.columns)): {len(df.columns)}")
Expected output:
Number of rows: 4
Number of columns: 3
Rows (using len): 4
Columns (using len(df.columns)): 3
Key lines explained:
df.shape— This is the most efficient way. It's a property that pandas computes lazily (it doesn't iterate through the data), so it's O(1) in time. The tuple(4, 3)tells us there are 4 rows and 3 columns. …
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