What Is pandas?

pandas is the most popular software library for data manipulation and data analysis for the Python programming languages.

Overview of pandas

pandas is an open-source software library built on Python for data analysis and data manipulation. The pandas library provides data structures designed specifically to handle tabular datasets with a simplified Python API. pandas is an extension of Python to process and manipulate tabular data, implementing operations such as loading, aligning, merging, and transforming datasets efficiently.

The popularity of pandas as a data analysis tool might be attributed to its versatility as well as efficient performance. The name "pandas" originates from the term "panel data," referring to datasets that span multiple time periods, emphasizing its focus on versatile data structures for handling real-world datasets.

With its support for structured data formats like tables, matrices, and time series, the pandas Python API provides tools to process messy or raw datasets into clean, structured formats ready for analysis. To achieve high performance, computationally intensive operations are implemented using C or Cython in the back-end source code. The pandas library is inherently not multi-threaded, which can limit its ability to take advantage of modern multi-core platforms and process large datasets efficiently. However, new libraries and extensions in the Python ecosystem can help address this limitation.

The pandas library integrates with other scientific tools within the broader Python data analysis ecosystem.

How Does pandas Work?

At the core of the pandas open-source library is the DataFrame data structure for handling tabular and statistical data. A pandas DataFrame is a two-dimensional, array-like table where each column represents values of a specific variable, and each row contains a set of values corresponding to those variables. The data stored in a DataFrame can encompass numeric, categorical, or textual types, enabling pandas to manipulate and process diverse datasets.

pandas facilitates importing and exporting datasets from various file formats, such as CSV, SQL, and spreadsheets. These operations, combined with its data manipulation capabilities, enable pandas to clean, shape, and analyze tabular and statistical data.

Ultimately, the DataFrame serves as the backbone of pandas, enabling users to manage and analyze structured datasets efficiently, from importing and exporting raw data to performing advanced data manipulation tasks for machine learning and beyond.

Pandas allows for importing and exporting tabular data in various formats, such as CSV, SQL, and spreadsheet files.

pandas also allows for various data manipulation operations and data cleaning features, including selecting a subset, creating derived columns, sorting, joining, filling, replacing, summary statistics, and plotting.

According to organizers of the Python Package Index—a repository of software for the Python programming language—pandas is well suited for working with several kinds of data, including:

  • Tabular data with heterogeneously-typed columns, as in an SQL table or spreadsheet.
  • Ordered and unordered (not necessarily fixed-frequency) time-series data.
  • Arbitrary matrix data (homogeneously typed or heterogeneous) with row and column labels.
  • Any other form of observational/statistical datasets. The data actually need not be labeled at all to be placed into a pandas data structure.

What Are the Benefits of pandas?

The pandas library offers numerous benefits to data scientists and developers, making it a valuable tool for data analysis and manipulation. Key benefits include:

  • Handling of missing data (NaN): pandas simplifies working with datasets containing missing data, represented as NaN, whether the data is numeric or non-numeric.
  • GroupBy functionality: pandas provides efficient GroupBy operations, enabling users to perform split-apply-combine workflows for data aggregation and transformation.
  • DataFrame size mutability: Columns can be added or removed from DataFrames or higher-dimensional data structures.
  • Automated and explicit data alignment: pandas ensures data alignment by automatically aligning objects like Series and DataFrames to their labels, simplifying computations.
  • Thorough Documentation: The simplified API and fully documented features lower the learning curve for pandas. The short, simple tutorialsand code samples enable new users to quickly start coding.
  • I/O tools: pandas supports importing and exporting data in various formats, such as CSV, Excel, SQL, and HDF5.
  • Visualization-ready datasets: pandas has straightforward visualization that can be plotted directly from the DataFrame object.
  • Flexible reshaping and pivoting: pandas simplifies reshaping and pivoting to single function calls on datasets to further prepare them for analysis or visualization.
  • Hierarchical axis labeling: pandas supports hierarchical indexing, allowing users to manage multi-level data structures within a single DataFrame.
  • Time-series functionality: pandas includes multiple time-series analysis functions, offering tools for date-range generation, frequency conversion, moving window calculations, and lag analysis.

What Are Real-World Applications of pandas?

As evidenced by its PyPi download stats, pandas has become a popular tool for data scientists and analysts, enabling efficient handling of datasets across various industries. Its capabilities for data analysis and manipulation make it a top choice for solving real-world problems.

  1. SQL Integration and Data Analysis
    pandas integrates with SQL databases, enabling users to read from and write to SQL tables directly within the pandas Python API. By importing data directly into a DataFrame, users can leverage pandas for data analysis while maintaining SQL for querying and managing datasets.
  2. Visualization and Insights
    pandas’ ability to clean, filter, and transform tabular data ensures that datasets are ready for advanced charting and plotting libraries, like Matplotlib and Seaborn. For instance, pandas can handle missing data and reformat time-stampedtime-series data to create meaningful trends and insights.
  3. Time-Series Analysis
    pandas has numerous time-series functions for tasks like analyzing stock prices, weather patterns, and IoT sensor readings. Its functionality includes date-range generation, frequency conversion, and advancedreshaping operations for temporal datasets.
  4. Complex Data Manipulation
    Tasks such as merging, joining, or concatenating multiple DataFrames are straightforward with pandas. The concat method, combined with tools like pandas append, enables combining disparate data sources. The library also provides GroupBy functionality to aggregate and transform data, supporting advanced split-apply-combine techniques.
  5. Tabular Data Transformation
    pandas simplifies the transformation of tabular data with features like reshaping, pivoting, and hierarchical indexing. For example, users can reshape their datasets to analyze sales performance across regions or pivot tables for a clearer view of customer behavior.
  6. Handling Missing Data
    Managing missing data is one of pandas' core strengths. Users can fill, interpolate, or drop NaN values directly within a DataFrame to create clean and complete datasets for analysis or integration into machine learning pipelines.

Python and pandas

Given that pandas is built on top of the Python programming language, it’s important to understand why Python is such a powerful tool for data science and analysis.

Python programming has grown in popularity since its creation in 1991, becoming a top language for web development, data analysis, and machine learning. Its simplicity and readable syntax allow both beginners and advanced users to focus on solving problems and avoid the complexities of lower-level languages. This ease of use is further enhanced by a large ecosystem of libraries and tools, including pandas, NumPy, Matplotlib, and Jupyter.

The pandas API leverages these strengths of Python, providing robust capabilities for data manipulation and analysis. Functions such as str methods for string operations and support for custom lambda functions enable users to write expressive algorithms directly within their workflows. Python’s compatibility with other libraries like NumPy allows for integration of numerical computations with pandas' data-handling capabilities.

Python's ecosystem extends to its ability to interface with external systems and services via API wrappers. This makes it easier to integrate pandas into larger data pipelines, whether working on local systems or cloud-based environments. For visualization, libraries like Matplotlib complement pandas, enabling clear and effective graphical representations of data.

The official docs for Python and pandas are valuable for learning the language and its libraries, offering comprehensive guides and code examples. Combined with interactive tools like Jupyter Notebooks, these resources make Python a popular choice for developing and testing data-driven algorithms.

By combining the flexibility of Python programming, the power of libraries like pandas and NumPy, and tools for visualization like Matplotlib, Python provides a cohesive environment for tackling complex data challenges with ease.

How Does GPU Acceleration Enhance pandas DataFrames?

While traditional CPUs are optimized for sequential, serial processing, GPUs feature a massively parallel architecture with thousands of smaller cores designed to handle multiple tasks simultaneously. This parallelism makes GPUs significantly faster than CPUs for processing large datasets and executing compute-intensive tasks. Their efficiency and low cost per FLOP (performance) have revolutionized compute-heavy workloads, especially in the context of data science and machine learning.

For data science tasks like processing a pandas DataFrame or performing DataFrame operations on massive datasets, GPU acceleration provides an advantage. Traditional tools like pandas, which typically run on CPUs, can now be optimized to leverage GPU power with zero code change through NVIDIA's cuDF library. cuDF, part of the NVIDIA RAPIDS™ data science platform, is a GPU DataFrame library that provides a pandas-like API for loading, filtering, and manipulating data. In earlier releases of cuDF, it was meant for GPU-only development workflows. Using cuDF, data scientists can get up to 50X faster performance on GPUs vs CPUs with zero code change to their pandas code. 

NVIDIA cuDF was built for data scientists who want to continue using pandas as data sizes grow into gigabytes and performance slows. When cuDF accelerates pandas, operations will run on the GPU if possible, and on the CPU (using pandas) otherwise. cuDF synchronizes between the GPU and CPU under the hood as needed. This enables a unified CPU/GPU experience to bring best-in-class performance to your pandas workflows. This design ensures that users familiar with pandas DataFrame workflows can transition to GPU-accelerated computing without code changes.

By enabling GPU-based processing for data preparation tasks like cleaning, transforming, and analyzing datasets, cuDF significantly reduces runtime bottlenecks. Its integration with machine learning tools like scikit-learn, combined with support for multi-GPU and multi-node deployments, allows users to process much larger datasets and scale efficiently. This capability transforms traditional ETL workflows, making it possible to accelerate pipelines from DataFrame manipulation to machine learning and even deep learning.

How to Get Started With Accelerated pandas?

Install NVIDIA RAPIDS

To get started with accelerated pandas, you first need to install NVIDIA RAPIDS. Please see our installation docs at RAPIDS Installation Guideto install cuDF and the required dependencies for your architecture.

Install pandas

After the appropriate NVIDIA RAPIDS libraries are installed, it’s time to install pandas. pandas can be installed with pip or conda as follows:

pip install pandas or conda install -c conda-forge pandas

Start coding with iPython or Jupyter

If you are using the iPython interpreter or in a Jupyter Notebook, add these lines before importing pandas:

%%load_ext cudf.pandas
import pandas as pd

Start coding with Python

If using the standard Python interpreter, add the following lines before importing pandas:

import cudf.pandas
cudf.pandas.install()
import pandas as pd

Next Steps

See how to get started with RAPIDS

Learn how to accelerate pandas with RAPIDS cuDF and seamlessly integrate GPU-acceleration into your data science workflows.

Dive deeper into RAPIDS cuDF

Learn more about how RAPIDS cuDF accelerates pandas on the NVIDIA Technical blog.

Watch Videos and Demos Accelerating pandas

Watch videos and cuDF on/off demos to see how RAPIDS accelerates pandas.