Double-digits

Notebook-Faithful Delta

Classic MNIST lab notes, rebuilt as one online engineering notebook.

The web app now follows the same progression as the old notebooks: examine one handwritten digit, compose two digits into a full 28x56 scene, and then push that scene into handwritten arithmetic with notebook-era divide semantics still intact.

Learning Objectives

  • Inspect raw MNIST evidence before asking the model to guess.
  • See direct whole-scene classification for two-digit composition.
  • Compare generated scenes, learned activations, and notebook-style prototype views.
  • Switch among notebook-derived presets without leaving the browser.

Single-digit Lab

This section mirrors the notebook setup cells: start with one MNIST digit, compare it to class means, and then inspect the learned first-layer and activation responses.

Notebook step Examine the data
Advanced preset notebook

Waiting for the first notebook run.

single digit example
Input scene

Feature Maps

Notebook-style intermediate activations rendered with viridis.

Prototype Notes

MNIST class means plus first-layer weight maps rendered with binary_r and bone.

Comparison Strip

The generated scene placed beside its notebook-grounded source evidence.

Two-digit Lab

This section follows the old doubleDigits and getDoubleDigits flow: two MNIST digits are merged into one wider image and classified directly as a whole scene rather than by post-hoc stitching.

Notebook step Make double digits
Advanced preset notebook

Waiting for the first notebook run.

double digit example
Whole 28x56 composition

Feature Maps

Layer-by-layer scene responses from the selected notebook-derived preset.

Prototype Notes

Left/right MNIST means plus weight maps for the first dense layer.

Comparison Strip

Source digits laid beside the composed scene so the whole-scene prediction can be checked by eye.

Arithmetic Lab

This section keeps the notebook arithmetic rules intact: addition, subtraction by larger-minus-smaller, multiplication, and division with the notebook 99 sentinel when the smaller digit is zero.

Notebook step Handwritten arithmetic
Advanced preset notebook

Waiting for the first notebook run.

arithmetic example
Operator-overlaid input
predicted arithmetic result
Predicted result raster

Feature Maps

Intermediate responses from the chosen arithmetic preset.

Prototype Notes

Class means, first-layer views, and arithmetic context from the notebook pipeline.

Comparison Strip

Input scene, source digits, operator glyph, and the predicted result image all in one notebook strip.