Notebook

A Notebook is a document-style Modellus model. Instead of placing shapes freely on a board, you write a vertical sequence of blocks — headings, text, expressions, charts, tables, sliders, and media — like an interactive lab report or worksheet.

Overview

Notebooks share the same calculation engine as the Board editor. Expression blocks define the mathematics of the model — using the same expression language as the Expression shape — and the remaining blocks display and control it. A notebook combines narrative (headings, text, images) with a live, playable simulation.

Every notebook has a header with a cover image, a title, the author name, and the date it was last modified. Click the cover image to upload a new one, and click the title to edit it.

Creating and Opening Notebooks

Notebooks are created from the Community page: click Create Notebook in the sidebar. Notebooks appear alongside board models on Community cards, marked with a notebook icon, and open in the notebook editor rather than the board editor.

Blocks

Content is added as blocks from the top toolbar. Each button appends a new block at the end of the notebook.

Block	Icon	Description
Header		A large heading for structuring the document
Text		A paragraph of text for explanations and narrative
Expression		A mathematical expression that is parsed into the model, exactly like the Expression shape
Chart		Plots terms of the model as the simulation runs, like the Chart shape
Table		Displays term values per iteration, like the Table shape
Simulation		Embedded simulation area (in development)
Gauge		Circular dial for a term (in development)
Slider		Interactive slider to adjust a value
Value		Numeric readout of a term (in development)
Media		An image embedded in the document
Question		Assessment question (in development)
Ruler		A scale to measure against, read linearly or over decades. The ruler object itself, in a block of its own
Protractor		A band of degrees to measure an angle against, markable in degrees, radians or turns. The protractor object itself, in a block of its own
Slope		Slope measurement tool (in development)

Blocks marked in development can be added and arranged, but currently render as placeholders.

Working with Blocks

Select — Click a block to select it. A context toolbar appears below the block with its specific options (terms to display, colors, and more).
Reorder — Use the grip handle on the left edge of a block to drag it to a new position. The context toolbar also offers move actions.
Style — Every block has a background color and a border color, available from the color button on its context toolbar.
Duplicate, copy, and paste — Blocks can be duplicated in place or copied to the clipboard and pasted after another block.
Delete — Remove a block from its context toolbar, or select it and press Delete.
Undo / redo — Adding, removing, moving, and editing blocks is undoable with the toolbar buttons or Ctrl+Z / Ctrl+Y (Cmd on macOS).

Running the Model

Notebook player toolbar with independent variable, playback controls, and playhead slider

The player toolbar at the bottom of the notebook drives the simulation, just as in the board editor:

Independent variable — Click the variable name (e.g. t) to rename it.
Start / Step — Click the start value to set the domain start and the iteration step.
End — Click the end value to set where the simulation stops.
Playback — Play/pause, stop, step backward/forward, and replay buttons, plus a playhead slider to scrub through iterations.

Chart, table, and slider blocks update live while the model plays.

Saving and Collaboration

Notebooks are saved to your account from the menu. Only the notebook's owner can save changes.
When a notebook you own is open, edits are synchronized in real time, so collaborators viewing the same notebook see changes as they happen.
The cover image is uploaded as the notebook's thumbnail when you save.

File Format

A notebook is stored like any other model, with an additional top-level notebook section in the model definition:

{
  "properties": { ... },
  "notebook": {
    "title": "Free Fall Lab",
    "author": "Author",
    "blocks": [
      { "id": 1, "type": "header", "content": "Free fall" },
      { "id": 2, "type": "text", "content": "We model a falling object..." },
      { "id": 3, "type": "expression", "content": "\\frac{dy}{dt}=v" }
    ]
  }
}

Each block carries an id, a type, its content, and styling properties such as backgroundColor and borderColor. See the Model Schema for the full model format.