In-browser REPL

The published documentation site ships a fully in-browser version of reASITIC — Python, NumPy, SciPy and the reasitic wheel all run via Pyodide inside your tab, no install required.

🚀 Launch the REPL

(If you’re reading this on GitHub the link above points to the deployed site at https://AL-255.github.io/reASITIC/repl/.)

What you can do

  • Pick a tech file (BiCMOS.tek or CMOS.tek) and one of the 13 geometry primitives ASITIC supports:

    Section

    Commands

    Single-trace primitives

    Wire, Capacitor, Ring, Via

    Single-port spirals

    Square (SQ), Polygon (SP), Multi-metal square (SQMM)

    Centre-tapped

    Symmetric square (SYMSQ), Symmetric polygon (SYMPOLY)

    Two-coil

    Transformer (TRANS) primary + secondary, Balun primary + secondary

  • Adjust the per-shape parameters (LEN / RADIUS / W / S / N / ILEN / SIDES / ORIENT / PHASE / EXIT metal …). The layout updates live.

  • Run the analysis routines:

    • L · R · Q at the chosen frequency

    • Pi-model extraction

    • S-parameter sweep with self-resonance estimate

    • .s2p / SPICE export buttons download the result

    • Geom info dumps the polygon set

  • Open the Python REPL tab to script against the live shape and tech objects:

    import reasitic
print(reasitic.summary())
print("L =", round(reasitic.compute_self_inductance(shape), 4), "nH")

CIF parity

Every shape in the REPL renders the exact same vertices the original 1999 ASITIC binary writes to its CIF / GDS output — verified by 91 vertex-for-vertex regression tests against the C-binary’s golden CIFs. What you see in the canvas is the layout the binary would emit.

How it works

The REPL is a static page with three pieces:

  1. Pyodide is fetched from the official CDN on first load (~30 MB, cached thereafter).

  2. The reasitic wheel and a small bridge (bridge.py) are loaded from the same directory (deployed at repl/wheels/ and repl/bridge.py).

  3. The UI (app.js, draw.js) calls into the bridge for build_shape, analyze_* and export_* and renders the polygons as SVG.

Nothing is sent off your machine after the initial Pyodide download. Everything — geometry, inductance, Pi-model, SPICE — runs in your browser.

Running the REPL locally

cd docs/repl
python -m http.server 8000
# then open http://localhost:8000/ in your browser

(A plain file:// URL won’t work because Pyodide / the wheel install need a real HTTP server for fetch().)