[Python] How to efficiently handle large datasets in Python using Pandas?

I am working with a large dataset (approximately 1 million rows) in Python using the Pandas library, and I am experiencing performance issues when performing operations such as filtering and aggregating data.

Here is a simplified version of my code:

import pandas as pd

# Load the dataset
df = pd.read_csv('large_dataset.csv')

# Example operation: Filtering and aggregating
result = df[df['column_name'] > threshold_value].groupby('another_column').mean()



I've tried using df.memory_usage(deep=True) to analyze memory usage and pd.read_csv() with the chunksize parameter to load the data in chunks, but I still face slow performance.

**What are some best practices for optimizing data processing with Pandas for large datasets? ** Any suggestions on techniques, alternative libraries, or specific functions that could help improve performance would be greatly appreciated!

What I Tried:

Memory Analysis: I used df.memory_usage(deep=True) to understand memory consumption and found that certain columns were using a lot of memory due to their data types.

1. 
   Loading Data in Chunks: I attempted to load the dataset in chunks using the chunksize parameter with pd.read_csv(). This allowed me to work with smaller parts of the dataset, but my filtering and aggregation operations remained slow.
   
   
2. 
   Data Type Optimization: I experimented with changing data types of certain columns to more memory-efficient types (e.g., converting float64 to float32), which helped reduce memory usage but didn’t significantly improve the processing time.
   
   
3. 
   What I Was Expecting: I expected that by analyzing memory usage and optimizing data types, along with loading data in chunks, I would see a noticeable improvement in the speed of my filtering and aggregation operations. However, the performance remains suboptimal, especially with the large size of the dataset.
   

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