Marey.Verso 0.7.0

Marey.Verso

The Verso notebook extension for Marey, a dimensionally-typed visualization system for F#.

This package is installed into the notebook host, not referenced from user code. With it, a cell whose value is a Figure displays the figure — no .Show(), no save-then-open, no display call:

#r "nuget: Marey.Html"

open Marey
open Marey.UnitsOfMeasure

Chart.line U.second U.metre t x
|> Chart.withTitle "Free fall"

Twelve types render: Figure, Film, Node, Color, Ramp, Color[], PaletteReport, Dim, U<'u>, IScaleErased, and a live figure, Live or Recorder.

A Film plays in the cell — an animation built with Marey.Anim and the scene { … } block displays as a looping flipbook rather than as a record field table, with no encoder installed and no video file on disk.

A live figure

A cell whose value is a Live, built with interact { … } from Marey.Interact, is a figure with controls. The extension opens an output channel for the cell, and each change the reader makes is stepped by the kernel and answered with the figure, or with the parts of it that changed. A drag zooms, a shift-drag pans, a double click resets, and the pointer's position is read in the axes' units. A save writes the figure at the state the reader left it in, with its controls disabled.

This needs a Verso whose formatter context carries output channels and the cell's id: a release 1.2.3 or newer. On an older host, or one without channels, the extension writes the same page with the controls disabled and opens nothing.

Installing

Verso's Extensions panel searches nuget.org, then unpacks the package into its own store and asks for approval — extensions are code that runs inside the notebook host, so approval is requested per version.

Installing it is not the same as referencing Marey

The two are separate steps and neither substitutes for the other. #r "nuget: Marey.Html" in a cell provides the types; the extension provides the rendering. Verso has no #r-time extension hook.

Without the extension nothing is lost except the convenience — render to SVG and Verso's built-in formatter draws it, with nothing installed:

figure |> Chart.render SvgBackend.render (Chart.size 720.0 450.0)

Why an extension is needed

Verso resolves output through formatters ordered by priority, and its F# formatter claims every record, union and tuple at priority 20. Figure is a record, so without something ranked above it a table of fields is displayed instead. This formatter sits at priority 30.

No reference to Marey

A Verso extension and the notebook's #r load into different AssemblyLoadContexts, so a Figure on one side and a Figure on the other would be two unequal types. The bridge is therefore reflective, which leaves this package with exactly one dependency — Verso.Abstractions — and keeps it working across Marey versions. A live figure's state crosses the same boundary as an opaque object that only Marey.Html looks inside.

• The guide
• Examples