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Pandas: working with MemoryError when attempting to concatenate multiple large DataFrames

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pandas dataframe memory-management Python

I've looked through the documentation and I'm still confused about I'm relatively new to this, so bear with me... After trying multiple solutions online, I still can't figure this out. I've been struggling with this for a few days now and could really use some help. I'm trying to concatenate several large DataFrames using pandas version 1.5.0, but I'm running into a `MemoryError`. My DataFrames are each around 2 million rows and have 10 columns, which I thought would be manageable, but it seems to exceed my system's memory limit. Here’s a snippet of the code I’m using: ```python import pandas as pd # Simulating large DataFrames dfs = [pd.DataFrame({'A': range(2000000), 'B': range(2000000, 4000000)}) for _ in range(5)] # Attempting to concatenate big_df = pd.concat(dfs, ignore_index=True) ``` When I run this, I get the following behavior message: ``` MemoryError: Unable to allocate 40.0 MiB for an array with shape (2000000, 10) and data type int64 ``` I’ve tried increasing my swap space and closing other applications to free up memory, but the question continues. Is there a more memory-efficient way to concatenate these DataFrames, or a strategy to handle large datasets more effectively with pandas? Any advice would be greatly appreciated! My development environment is Windows. Any advice would be much appreciated. This is for a application running on Linux. Is there a better approach? My team is using Python for this REST API. How would you solve this?