1# Concept Collection
3A set of small, independent projects: interactive demos, teaching material, and
4research code. Most run directly in the browser with nothing to install, and
5many are written in MATLAB syntax and run there via [numbl](https://numbl.org).
7Projects are grouped below by **application area** — sampling, geometry and
8meshing, visual math, neurophysiology, data compression, physics, and more —
9rather than by the technology behind them. The most interactive and visual
10demos come first; utilities, datasets, and templates are toward the end. Each
11links to its repository, and to a live page where there is one.
13## Monte Carlo & sampling
15- **[hitandrun-interactive](https://github.com/concept-collection/hitandrun-interactive)**
16 ([live](https://concept-collection.github.io/hitandrun-interactive/#figure/sampler)).
17 Hit-and-run MCMC sampling of a 2-D convex region, with React driving a numbl
18 script. Resample, make new regions, or play a step-by-step movie of the
19 algorithm.
20- **[walnuts-interactive](https://github.com/concept-collection/walnuts-interactive)**
21 ([live](https://concept-collection.github.io/walnuts-interactive/#figure/sampler)).
22 WALNUTS (the within-orbit adaptive leapfrog No-U-Turn Sampler) drawing from a
23 2-D banana target, with React driving a numbl script. Tune the leapfrog step
24 and error tolerance, or play a step-by-step movie of the orbit-building.
25- **[stan-web-ide](https://github.com/concept-collection/stan-web-ide)**
26 ([live](https://concept-collection.github.io/stan-web-ide/)).
27 Run [Stan](https://mc-stan.org) sampling in your browser, in a VS Code-style
28 IDE.
30## Peer-to-peer shared state
32- **[hitandrun-commonview](https://github.com/concept-collection/hitandrun-commonview)**
33 ([live](https://concept-collection.github.io/hitandrun-commonview/)).
34 The hit-and-run figure with a single live view shared by all visitors over a
35 WebRTC mesh; one peer runs the sampler via numbl and broadcasts to the rest.
36- **[commonview](https://github.com/concept-collection/commonview)**
37 ([live](https://concept-collection.github.io/commonview/)).
38 A minimal peer-to-peer page where every visitor shares one state (a counter):
39 nostr discovery, a WebRTC mesh, and a central-peer authority. The basis for
40 hitandrun-commonview.
42## Geometry, meshing & PDE solvers
44- **[surfacefun-interactive](https://github.com/concept-collection/surfacefun-interactive)**
45 ([live](https://concept-collection.github.io/surfacefun-interactive/)).
46 surfacefun demos with live sliders, where React and three.js drive a numbl
47 script. Refine a cubed-sphere mesh or scale a tangent vector field and watch
48 it update.
49- **[mesh-studio](https://github.com/concept-collection/mesh-studio)**
50 ([live](https://concept-collection.github.io/mesh-studio/)).
51 Build CAD primitives or import STEP/IGES with
52 [OpenCASCADE.js](https://ocjs.org/), then inspect them in 3D — including each
53 face's true NURBS surface (polynomials on faces), not just its triangulation.
54- **[mesh-converter](https://github.com/concept-collection/mesh-converter)**
55 ([live](https://concept-collection.github.io/mesh-converter/)).
56 Convert meshes between 19 formats (PLY, OBJ, STL, VTK, Gmsh, XDMF, …) with
57 [meshio](https://github.com/nschloe/meshio) running in-browser on Pyodide;
58 inspect meshes in 3D and see what a lossy export would drop.
59- **[mesh-pde-solver](https://github.com/concept-collection/mesh-pde-solver)**
60 ([live](https://concept-collection.github.io/mesh-pde-solver/)).
61 Upload a quad surface mesh and solve Poisson or Helmholtz problems on it
62 with [surfacefun](https://github.com/danfortunato/surfacefun), entirely in
63 the browser; the solution renders in a rotatable 3D view.
64- **[qhull-wasm-demo](https://github.com/concept-collection/qhull-wasm-demo)**
65 ([live](https://concept-collection.github.io/qhull-wasm-demo/)).
66 Demos and benchmarks for [qhull-wasm](https://github.com/magland/qhull-wasm),
67 which compiles [Qhull](http://www.qhull.org) to WebAssembly. Includes 2-D
68 Delaunay triangulation, 3-D convex hull, and a Delaunay benchmark with
69 matching scripts for MATLAB, Octave, and numbl.
70- **[numbl-distmesh](https://github.com/concept-collection/numbl-distmesh)**
71 ([live](https://concept-collection.github.io/numbl-distmesh/)).
72 Every example from Persson and Strang's
73 [DistMesh](https://github.com/popersson/DistMesh), meshing 2-D regions and
74 surfaces from signed distance functions.
75- **[numbl-surfacefun-intro](https://github.com/concept-collection/numbl-surfacefun-intro)**
76 ([live](https://concept-collection.github.io/numbl-surfacefun-intro/)).
77 An introduction to [surfacefun](https://github.com/danfortunato/surfacefun),
78 which computes with functions on surfaces and solves PDEs on them to high
79 order.
80- **[numbl-chunkie](https://github.com/concept-collection/numbl-chunkie)**
81 ([live](https://concept-collection.github.io/numbl-chunkie/)).
82 Examples for [chunkie](https://github.com/fastalgorithms/chunkie): building
83 chunker geometries in 2-D and solving Laplace, Helmholtz, and Stokes boundary
84 integral equations.
85- **[abc-step-1000](https://github.com/concept-collection/abc-step-1000)**
86 ([live](https://concept-collection.github.io/abc-step-1000/)).
87 The first 1000 STEP files from the
88 [ABC dataset](https://deep-geometry.github.io/abc-dataset/) of CAD models
89 (Koch et al., CVPR 2019), served gzip-compressed with a JSON manifest for
90 direct download.
92## Number theory & visual math
94- **[finite-field-visualizer](https://github.com/concept-collection/finite-field-visualizer)**
95 ([live](https://concept-collection.github.io/finite-field-visualizer/)).
96 Color-coded multiplication tables over finite (prime) fields. Step through the
97 primes to watch the structure change.
98- **[gcd-visualizer](https://github.com/concept-collection/gcd-visualizer)**
99 ([live](https://concept-collection.github.io/gcd-visualizer/)).
100 A heatmap of the greatest common divisor of every pair (i, j), laid out as a
101 color-coded table.
103## Neurophysiology data & remote access
105- **[remote-hdf5-lazy-read](https://github.com/concept-collection/remote-hdf5-lazy-read)**
106 ([live](https://concept-collection.github.io/remote-hdf5-lazy-read/)).
107 Shows how [neurosift](https://neurosift.app/) browses large remote
108 [NWB](https://www.nwb.org/)/HDF5 files in the browser using HTTP range
109 requests, with no full download and no backend.
110- **[dandiset_000986](https://github.com/concept-collection/dandiset_000986)**
111 ([visualizations](https://concept-collection.github.io/dandiset_000986/)).
112 Reproducible figures and visualizations for
113 [DANDI Dandiset 000986](https://dandiarchive.org/dandiset/000986), a set of
114 mouse auditory cortex recordings.
116## Scientific data compression
118- **[ans-visualizer](https://github.com/concept-collection/ans-visualizer)**
119 ([live](https://concept-collection.github.io/ans-visualizer/)).
120 A step-by-step visualizer for the Asymmetric Numeral Systems (ANS)
121 entropy-coding algorithm ([Duda et al., 2015](https://ieeexplore.ieee.org/abstract/document/7170048)).
122- **[benchcompress](https://github.com/concept-collection/benchcompress)**
123 ([results](https://concept-collection.github.io/benchcompress/),
124 [paper (WIP)](https://concept-collection.github.io/benchcompress/paper)).
125 A benchmarking framework that measures compression ratio and encode/decode
126 throughput for compression algorithms on scientific data arrays.
127- **[ephys_compression_tests](https://github.com/concept-collection/ephys_compression_tests)**
128 ([results](https://concept-collection.github.io/ephys_compression_tests/)).
129 Compression benchmarks for electrophysiology recordings.
131## Physics & quantum systems
133- **[numbl-quantum-optics](https://github.com/concept-collection/numbl-quantum-optics)**
134 ([live](https://concept-collection.github.io/numbl-quantum-optics/)).
135 Runnable scripts accompanying the article "Quantum optics in MATLAB"
136 ([arXiv:2309.14354](https://arxiv.org/abs/2309.14354)), covering quantum
137 states, operators, and dynamics.
138- **[numbl-open-quantum-systems](https://github.com/concept-collection/numbl-open-quantum-systems)**
139 ([live](https://concept-collection.github.io/numbl-open-quantum-systems/)).
140 Code from "Coding closed and open quantum systems in MATLAB"
141 ([arXiv:1911.04906](https://arxiv.org/abs/1911.04906)), including Ising
142 dynamics, cavity-QED phase transitions, and Lindblad and non-Markovian
143 evolution.
145## Image processing
147- **[numbl-image-filter](https://github.com/concept-collection/numbl-image-filter)**
148 ([live](https://concept-collection.github.io/numbl-image-filter/)).
149 Upload an image, write a MATLAB-syntax filter, and run it on the image in the
150 browser.
152## numbl platform: templates & tooling
154Utilities and starting points for building your own
155[numbl](https://numbl.org) projects.
157- **[numbl-web-ide](https://github.com/concept-collection/numbl-web-ide)**
158 ([live](https://concept-collection.github.io/numbl-web-ide/)).
159 Run MATLAB-syntax .m files in your browser, in a VS Code-style IDE.
160- **[jupyterlite-numbl-kernel](https://github.com/concept-collection/jupyterlite-numbl-kernel)**
161 ([live](https://concept-collection.github.io/jupyterlite-numbl-kernel/)).
162 A JupyterLite kernel that runs numbl in notebook cells entirely in the
163 browser, with inline figures and mip packages.
164- **[numbl-figure-viewer](https://github.com/concept-collection/numbl-figure-viewer)**
165 ([live](https://concept-collection.github.io/numbl-figure-viewer/)).
166 Open and explore a figure exported from numbl, including its underlying data.
167- **[numbl-project-example](https://github.com/concept-collection/numbl-project-example)**
168 ([live](https://concept-collection.github.io/numbl-project-example/)).
169 A minimal numbl project deployed to GitHub Pages, meant as a starting
170 template.
171- **[numbl-embed-example](https://github.com/concept-collection/numbl-embed-example)**
172 ([live](https://concept-collection.github.io/numbl-embed-example/)).
173 Shows how to embed editable, runnable numbl scripts inside Markdown rendered
174 on GitHub Pages.