Write a program in Python to create a panel from a dictionary of dataframe and print the maximum value of the first column

Pandas Panel was a 3-dimensional data structure in older versions of pandas. Though deprecated, understanding how to work with multi-dimensional data and extract maximum values from specific axes remains valuable for data analysis.

Problem Statement

We need to create a panel from a dictionary of DataFrames and find the maximum value in the first column across all items in the panel.

Solution Approach

To solve this problem, we will follow these steps ?

• Create a dictionary with DataFrame containing random data

• Convert the dictionary to a Panel structure

• Use minor_xs() to select the first column across all items

• Apply max() to find the maximum value

Implementation

import pandas as pd
import numpy as np

# Create dictionary with DataFrame
data = {'Column1': pd.DataFrame(np.random.randn(5, 3))}

# Create Panel from dictionary
p = pd.Panel(data)

print("Panel values:")
print(p['Column1'])

print("maximum value of first column is:")
print(p.minor_xs(0).max())

Understanding the Code

Let's break down the key components ?

• np.random.randn(5, 3) creates a 5x3 DataFrame with random values

• pd.Panel(data) constructs a 3D panel from the dictionary

• minor_xs(0) selects the first column (index 0) across all items

• max() returns the maximum value from the selected column

Expected Output

Panel values:
          0         1         2
0  0.914209 -0.665899 -0.703097
1 -1.375634 -0.164529 -0.673326
2  1.377292  0.692793  0.390777
3 -0.899618 -1.163681  0.954463
4  0.025898  0.832265  0.173535

maximum value of first column is:
Column1    1.377292
dtype: float64

Key Points

• Panel structure allows 3D data manipulation with items, major_axis, and minor_axis

• The minor_xs() method extracts data along the minor axis (columns)

• Random data will produce different results each time the code runs

Conclusion

This example demonstrates how to create a Panel from dictionary data and extract maximum values using axis selection. Though Panel is deprecated, the concepts of multi-dimensional data manipulation remain relevant in modern data analysis.