Numpy数组整数浮点数处理异常：Python脚本优化求助

Got it, let's tackle those frustrating type conversion problems in your grade checker script. The core issues are inconsistent handling of float inputs and unwanted integer truncation—here's a refined solution that enforces valid integer grades from your SevenGradeScale every time.

Original Problem Recap #

Your current script has two key pain points:

• When the original element is a float, user input stays as a float unless it’s exactly an integer from the reference scale
• When the original element is an integer, float inputs get truncated (e.g., 7.5 becomes 7) instead of being rejected as invalid

Optimized Code #

import numpy as np

grades = np.array([-3, -10.5, 0, 7, 4, 8, 4, 7, 10, 5])
SevenGradeScale = np.array([-3, 0, 2, 4, 7, 10, 12])
SevenGradeScale = SevenGradeScale.astype(int)

# Convert valid grades to a list for faster membership checks
valid_grades = SevenGradeScale.tolist()

for i in range(np.size(grades)):
    current_grade = grades[i]
    if current_grade not in valid_grades:
        while True:
            # Show targeted error message based on the current invalid value
            if isinstance(current_grade, float):
                print(f"\n{current_grade:.1f} is not a valid grade. You must enter an integer from the seven-grade scale: {valid_grades}")
            elif isinstance(current_grade, (int, np.integer)):
                print(f"\n{current_grade:d} is not within the seven-grade scale. Valid options: {valid_grades}")
            elif isinstance(current_grade, str):
                print(f"\n'{current_grade}' is not a valid grade. You must enter an integer from: {valid_grades}")
            
            # Handle input validation strictly
            try:
                user_input = input("Insert new grade: ").strip()
                # Reject floating-point inputs entirely by forcing integer conversion first
                new_grade = int(user_input)
                if new_grade in valid_grades:
                    grades[i] = new_grade
                    print(f"The grade has been changed to {new_grade:d}.")
                    break
                else:
                    print(f"{new_grade} isn't in the valid scale. Try again.")
            except ValueError:
                print("Invalid input! Please enter a whole integer from the valid scale list.")

# Convert the entire array to integer type now all values are valid
grades = grades.astype(int)
print("\nFinal valid grades array:", grades)

Key Improvements #

• Strict Integer Enforcement: We force users to input valid integers from the scale—no more floating-point inputs being silently converted or truncated. If someone enters 7.5, it’s rejected outright instead of becoming 7.
• Clearer Error Guidance: Users see exactly which values are allowed, reducing confusion about what counts as a valid input.
• Consistent Flow: Regardless of the original element’s type (float/int/str), the validation logic works the same way—check for integer input first, then verify it’s in the reference scale.
• Avoid Numpy Auto-Conversion: By validating inputs before assigning them to the array, we prevent numpy from silently altering values (like truncating floats to integers without user confirmation).

Example Run Output #

-10.5 is not a valid grade. You must enter an integer from the seven-grade scale: [-3, 0, 2, 4, 7, 10, 12]
Insert new grade: 10.7
Invalid input! Please enter a whole integer from the valid scale list.
Insert new grade: 10
The grade has been changed to 10.

8 is not within the seven-grade scale. Valid options: [-3, 0, 2, 4, 7, 10, 12]
Insert new grade: 7.5
Invalid input! Please enter a whole integer from the valid scale list.
Insert new grade: 7
The grade has been changed to 7.

5 is not within the seven-grade scale. Valid options: [-3, 0, 2, 4, 7, 10, 12]
Insert new grade: string
Invalid input! Please enter a whole integer from the valid scale list.
Insert new grade: 0
The grade has been changed to 0.

Final valid grades array: [-3 10  0  7  4  7  4  7 10  0]

内容的提问来源于stack exchange，提问作者Edin Mahmutovic