pocketflow/cookbook/pocketflow-nested-batch/README.md

PocketFlow Nested BatchFlow Example

This example demonstrates Nested BatchFlow using a simple school grades calculator.

What this Example Does

Calculates average grades for:

1. Each student in a class
2. Each class in the school

Structure

school/
├── class_a/
│   ├── student1.txt  (grades: 7.5, 8.0, 9.0)
│   └── student2.txt  (grades: 8.5, 7.0, 9.5)
└── class_b/
    ├── student3.txt  (grades: 6.5, 8.5, 7.0)
    └── student4.txt  (grades: 9.0, 9.5, 8.0)

How it Works

1. Outer BatchFlow (SchoolBatchFlow)

   • Processes each class folder
   • Returns parameters like: {"class": "class_a"}

2. Inner BatchFlow (ClassBatchFlow)

   • Processes each student file in a class
   • Returns parameters like: {"student": "student1.txt"}

3. Base Flow

   • Loads student grades
   • Calculates average
   • Saves result

Running the Example

pip install -r requirements.txt
python main.py

Expected Output

Processing class_a...
- student1: Average = 8.2
- student2: Average = 8.3
Class A Average: 8.25

Processing class_b...
- student3: Average = 7.3
- student4: Average = 8.8
Class B Average: 8.05

School Average: 8.15

Key Concepts

1. Nested BatchFlow: One BatchFlow inside another
2. Parameter Inheritance: Inner flow gets parameters from outer flow
3. Hierarchical Processing: Process data in a tree-like structure