Javascript – Python Pandas equivalent in JavaScript

javascriptpandaspython

With this CSV example:

   Source,col1,col2,col3
   foo,1,2,3
   bar,3,4,5

The standard method I use Pandas is this:

  1. Parse CSV

  2. Select columns into a data frame (col1 and col3)

  3. Process the column (e.g. avarage the values of col1 and col3)

Is there a JavaScript library that does that like Pandas?

Best Solution

This wiki will summarize and compare many pandas-like Javascript libraries.

In general, you should check out the d3 Javascript library. d3 is very useful "swiss army knife" for handling data in Javascript, just like pandas is helpful for Python. You may see d3 used frequently like pandas, even if d3 is not exactly a DataFrame/Pandas replacement (i.e. d3 doesn't have the same API; d3 doesn't have Series / DataFrame which behave like in pandas)

Ahmed's answer explains how d3 can be used to achieve some DataFrame functionality, and some of the libraries below were inspired by things like LearnJsData which uses d3 and lodash.

As for DataFrame-style data transformation (splitting, joining, group by etc) , here is a quick list of some of the Javascript libraries.

Note some libraries are Node.js aka Server-side Javascript, some are browser-compatible aka client-side Javascript, and some are Typescript. So use the option that's right for you.

  • danfo-js
    • From Vignesh's answer
    • danfo (which is often imported and aliased as dfd); has a basic DataFrame-type data structure, with the ability to plot directly
    • Built by the team at Tensorflow: "One of the main goals of Danfo.js is to bring data processing, machine learning and AI tools to JavaScript developers. ... Open-source libraries like Numpy and Pandas..."
    • pandas is built on top of numpy; likewise danfo-js is built on tensorflow-js
  • pandas-js
    • UPDATE The pandas-js repo has not been updated in awhile
    • From STEEL and Feras' answers
    • "pandas.js is an open source (experimental) library mimicking the Python pandas library. It relies on Immutable.js as the NumPy logical equivalent. The main data objects in pandas.js are, like in Python pandas, the Series and the DataFrame."
  • dataframe-js
    • "DataFrame-js provides an immutable data structure for javascript and datascience, the DataFrame, which allows to work on rows and columns with a sql and functional programming inspired api."
  • data-forge
  • jsdataframe
    • "Jsdataframe is a JavaScript data wrangling library inspired by data frame functionality in R and Python Pandas."
  • dataframe
    • "explore data by grouping and reducing."

Then after coming to this question, checking other answers here and doing more searching, I found options like:

  • Apache Arrow in JS
    • Thanks to user Back2Basics suggestion:
    • "Apache Arrow is a columnar memory layout specification for encoding vectors and table-like containers of flat and nested data. Apache Arrow is the emerging standard for large in-memory columnar data (Spark, Pandas, Drill, Graphistry, ...)"
  • Observable
    • At first glance, seems like a JS alternative to the IPython/Jupyter "notebooks"
    • Observable's page promises: "Reactive programming", a "Community", on a "Web Platform"
    • See 5 minute intro here
  • portal.js (formerly recline; from Rufus' answer)
    • MAY BE OUTDATED: Does not use a "DataFrame" API
    • MAY BE OUTDATED: Instead emphasizes its "Multiview" (the UI) API, (similar to jQuery/DOM model) which doesn't require jQuery but does require a browser! More examples
    • MAY BE OUTDATED: Also emphasizes its MVC-ish architecture; including back-end stuff (i.e. database connections)
  • js-data
    • Really more of an ORM! Most of its modules correspond to different data storage questions (js-data-mongodb, js-data-redis, js-data-cloud-datastore), sorting, filtering, etc.
    • On plus-side does work on Node.js as a first-priority; "Works in Node.js and in the Browser."
  • miso (another suggestion from Rufus)
  • AlaSQL
    • "AlaSQL" is an open source SQL database for Javascript with a strong focus on query speed and data source flexibility for both relational data and schemaless data. It works in your browser, Node.js, and Cordova."
  • Some thought experiments:

Here are the criteria we used to consider the above choices

  • General Criteria
    • Language (NodeJS vs browser JS vs Typescript)
    • Dependencies (i.e. if it uses an underlying library / AJAX/remote API's)
    • Actively supported (active user-base, active source repository, etc)
    • Size/speed of JS library
  • Panda's criterias in its R comparison
    • Performance
    • Functionality/flexibility
    • Ease-of-use
  • Similarity to Pandas / Dataframe API's
    • Specifically hits on their main features
    • Data-science emphasis
    • Built-in visualization functions
    • Demonstrated integration in combination with other tools like Jupyter (interactive notebooks), etc