JavaScript

JavaScript was made for web browsers, and Node.js runs it on servers and the command line. Its standard library has no numeric or data tools, so data science in JavaScript usually means packages from npm. npm is removed from this image, so none can be installed, and the work falls to array methods like map, filter, and reduce, plus the Math object.

Each file here is an ES module that imports readFileSync from node:fs. Node treats a .js file that uses import as a module even with no package.json beside it, so no flag is needed.

Quirks

• There is one number type, a 64-bit float: typeof 3 and typeof 3.5 are both "number", and 7 / 2 is 3.5.
• Node has no CSV parser among its built-in modules, so implementations here split lines on commas by hand.
• sort() with no comparator compares as strings: [10, 9, 1].sort() is [1, 10, 9]. Pass (a, b) => a - b to sort numbers.
• == on arrays compares identity, not contents: [1, 2] == [1, 2] is false.

git clone https://github.com/qnixon/dswithx.git
cd dswithx
python3 harness/run_tests.py --language javascript