1. Imports:

   • tkinter: Tkinter is the standard GUI library for Python. It provides classes for creating GUI applications.
   • ttk: The ttk module provides access to the Tk themed widget set.
   • messagebox: This module provides a simple way to create message boxes.

2. Class Definition:

   • AHP_GUI: This class represents the main application window for the AHP analysis.

3. Initialization (__init__ method):

   • Sets up the main application window (root) with a title.
   • Defines the criteria and alternatives for the AHP analysis.
   • Creates frames (criteria_frame and alternatives_frame) to organize the input fields for criteria weights and alternative scores.
   • Initializes variables to store criteria weights (criteria_weights) and alternative scores (alternative_scores).
   • Creates input fields (Entry widgets) for users to input criteria weights and alternative scores.
   • Creates a "Calculate" button to trigger the AHP calculation process.

4. Pairwise Comparison (pairwise_comparison method):

   • This method performs pairwise comparison of criteria weights.
   • It creates a pairwise comparison matrix based on the user-provided weights.
   • The pairwise comparison matrix is symmetric, and each element represents the ratio of the weight of one criterion to another.

5. Calculate Weights (calculate_weights method):

   • This method calculates the weights of criteria.
   • It takes the pairwise comparison matrix as input.
   • Uses NumPy's eigenvector function to calculate the principal eigenvector of the pairwise comparison matrix.
   • Normalizes the eigenvector to obtain the criteria weights.

6. Normalize Scores (normalize_scores method):

   • This method normalizes the scores of alternatives.
   • It ensures that the sum of scores adds up to 1, making them comparable.
   • This step is necessary to standardize scores across different criteria.

7. Calculate (calculate method):

   • This method is executed when the user clicks the "Calculate" button.
   • Retrieves criteria weights and alternative scores from the input fields.
   • Performs pairwise comparisons for criteria weights.
   • Calculates criteria weights.
   • Normalizes alternative scores.
   • Ranks alternatives based on their normalized scores.
   • Displays the ranked alternatives in a message box.

8. Main Window:

   • Creates the main Tkinter window (root).
   • Initializes the AHP_GUI class with the main window.
   • Enters the Tkinter event loop, allowing the GUI to respond to user interactions.

Overall, this code provides a graphical interface for users to input criteria weights and alternative scores, performs AHP calculations, and displays the ranked alternatives based on the analysis.