如何在Python的Sum类中实现add方法的链式调用以逐个处理列表元素

Got it, let's break down how to modify your Sum class to match the Keras-style sequential add() pattern with chaining support. Here's a straightforward implementation:

Modified Sum Class Code #

class Sum:
    def __init__(self):
        # Initialize our cumulative total to start at 0
        self.total = 0

    def add(self, num):
        # Add the single input number to our running total
        self.total += num
        # Return the instance itself to enable method chaining
        return self

    def get_total(self):
        # Helper method to safely retrieve the final sum
        return self.total

How to Use It #

• Initialize the class:

  sum_obj = Sum()
  

• Chain multiple add() calls (just like adding layers in Keras Sequential):

  sum_obj.add(5).add(8).add(2)
  

• Get the final sum:

  print(sum_obj.get_total())  # Output: 15
  

Key Details Explained #

• Cumulative storage: We use self.total in the constructor to keep track of the running sum across all add() calls.
• Chaining magic: The add() method returns self (the current instance of Sum). This lets you call another add() method immediately after the first, since you're operating on the same object every time.
• Encapsulation: The get_total() method is optional but recommended—instead of directly accessing sum_obj.total, using a method keeps your class's internal state encapsulated and makes future changes easier.

This setup mirrors the Keras Sequential workflow you referenced: you start with an empty instance, then build up your sum by adding elements one at a time, either via separate lines (sum_obj.add(5); sum_obj.add(8)) or chained calls.

内容的提问来源于stack exchange，提问作者Centy