{
 "cells": [
  {
   "cell_type": "markdown",
   "id": "intro-title",
   "metadata": {},
   "source": [
    "# MATLAB syntax, entirely in your browser\n",
    "\n",
    "This notebook runs on the **numbl kernel for JupyterLite**. Every cell executes\n",
    "in a Web Worker in *your* browser tab — there is no server and no kernel\n",
    "process behind this page, and nothing to install.\n",
    "\n",
    "The engine is [numbl](https://github.com/flatironinstitute/numbl), an\n",
    "open-source MATLAB-syntax language implementation in TypeScript.\n",
    "\n",
    "Run the cells below with **Shift+Enter**."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "intro-matrix",
   "metadata": {},
   "outputs": [],
   "source": [
    "A = [4 2 1; 2 5 3; 1 3 6]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "intro-solve",
   "metadata": {},
   "outputs": [],
   "source": [
    "% Variables persist across cells; solve a linear system with backslash\n",
    "b = [1; 2; 3];\n",
    "x = A \\ b\n",
    "residual = norm(A*x - b)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "intro-indexing",
   "metadata": {},
   "outputs": [],
   "source": [
    "% MATLAB indexing: rows, and logical masks\n",
    "A(2, :)\n",
    "A(A > 3)'"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "intro-loop",
   "metadata": {},
   "outputs": [],
   "source": [
    "total = 0;\n",
    "for k = 1:10\n",
    "    total = total + k^2;\n",
    "end\n",
    "fprintf('sum of squares 1..10 = %d\\n', total);"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "intro-anon",
   "metadata": {},
   "outputs": [],
   "source": [
    "% Anonymous functions work in cells (named functions belong in .m files)\n",
    "f = @(t) exp(-t) .* cos(2*pi*t);\n",
    "vals = arrayfun(f, 0:0.5:2)"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "1e814d6c",
   "source": "## Named functions live in `.m` files\n\nnumbl's cells work like the MATLAB console: you can't define a *named*\nfunction directly in a cell. Instead, put it in a `.m` file next to the\nnotebook — this kernel syncs `.m` files from the file browser into the\nsession before every cell runs, so functions defined there are callable\nimmediately, and edits take effect the next time you run a cell.\n\nThis notebook ships with [statsutils.m](./statsutils.m) — open it, and try\nediting it (e.g. add a `median` field) while the cell below is still there.",
   "metadata": {}
  },
  {
   "cell_type": "code",
   "id": "55d6bb19",
   "source": "data = [2 4 4 4 5 5 7 9];\ns = statsutils(data);\nfprintf('mean=%.4f std=%.4f range=%.4f\\n', s.mean, s.std, s.range);",
   "metadata": {},
   "execution_count": null,
   "outputs": []
  },
  {
   "cell_type": "markdown",
   "id": "intro-next",
   "metadata": {},
   "source": [
    "Next: [plotting](./02-plotting.ipynb) and\n",
    "[installing packages](./03-packages.ipynb) — both also fully client-side."
   ]
  }
 ],
 "metadata": {
  "kernelspec": {
   "display_name": "MATLAB (numbl)",
   "language": "matlab",
   "name": "numbl"
  },
  "language_info": {
   "codemirror_mode": "octave",
   "file_extension": ".m",
   "mimetype": "text/x-octave",
   "name": "matlab",
   "pygments_lexer": "matlab"
  }
 },
 "nbformat": 4,
 "nbformat_minor": 5
}