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lolviz

BSD-3-ClauseJupyter Notebook1.4

A Python data-structure visualization tool for lists, dictionaries, trees, and call stacks, designed for Jupyter notebooks and presentations.

GitHubGitHub
841 stars47 forks0 contributors

What is lolviz?

lolviz is a Python library that creates visualizations of data structures such as lists, dictionaries, trees, and call stacks. It helps developers and educators illustrate how data is organized in memory, making it easier to explain concepts, debug structures, or present findings in Jupyter notebooks.

Target Audience

Educators, students, and developers who need to visualize data structures for teaching, learning, or debugging purposes, particularly within Jupyter notebook environments.

Value Proposition

It offers a straightforward, Python-native way to generate clean, informative diagrams of complex data layouts without external tools, specifically optimized for interactive use in presentations and educational content.

Overview

A simple Python data-structure visualization tool for lists of lists, lists, dictionaries; primarily for use in Jupyter notebooks / presentations

Use Cases

Best For

  • Teaching data structure concepts in Python courses
  • Visualizing linked lists or binary trees in Jupyter notebooks
  • Debugging complex nested dictionaries and lists
  • Presenting algorithm state changes during talks
  • Exploring machine learning data structures like decision trees
  • Illustrating function call stacks and variable references

Not Ideal For

  • Production systems requiring real-time, interactive data structure monitoring
  • Projects needing highly customized visual styles or integration with dynamic web frameworks
  • Environments where installing Graphviz is impractical or prohibited

Pros & Cons

Pros

Jupyter Notebook Integration

Displays visualizations directly in Jupyter notebooks without extra steps, as demonstrated in the usage examples, making it ideal for interactive teaching.

Comprehensive Data Structure Coverage

Supports lists, dictionaries, trees, call stacks, and NumPy arrays with specialized functions like treeviz() and callsviz(), covering common educational needs.

Educational Optimization

Designed for clarity in memory layout, inspired by Python Tutor, with features like vertical list displays for wide data to avoid distortion.

Customizable Preferences

Allows adjustment of string length, list width, and float precision through global prefs, enhancing readability for different data types.

Cons

External Dependency on Graphviz

Requires separate installation of Graphviz (e.g., brew install graphviz), which can complicate setup and add an external tool dependency.

Limited Tree Visualization Orientation

For object graphs, trees are displayed left-to-right instead of top-down, as noted in the README, which may not align with standard computer science depictions.

Restricted Array Dimensionality

matrixviz() only handles 1D and 2D NumPy arrays, lacking support for higher-dimensional data common in machine learning.

Static Output Limitations

Generates static images via Graphviz, missing interactive features like zoom or real-time updates, reducing utility for dynamic debugging sessions.

Frequently Asked Questions

Quick Stats

Stars841
Forks47
Contributors0
Open Issues4
Last commit4 years ago
CreatedSince 2017

Tags

#data-structures#teaching-tool#python#jupyter-notebook#graphviz#data-visualization#call-stack#debugging-tool

Built With

G
GraphViz
P
Python

Included in

Jupyter4.6k
Auto-fetched 4 hours ago

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