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Data

Datasets as an environment reads them: a column resolved to numbers, dates, slices or categories, the axis presets over them, and a series entry.

@internote/canvas-sdk95 exports

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An author attaches datasets to a document and binds an attribute to a column. The environment reads them through ctx.datasets.

A column arrives as text. These read a bound column as values:

resolveNumericColumn reads it as numbers.
resolveCategoricalColumn reads it as positions on a categorical axis.
resolveSliceColumn reads dates, months, weekdays and times as numbers a control can step through.
datasetColumnKind says which kind of column it is.

resolveNumber and resolveInterval evaluate a value that may be a number, a date or an expression, at the current parameter values.

For long-format data — one row per thing per slice — buildSlicedSeries groups a key, a slice and a value column into a SlicedSeries, and seriesAt reads it at one slice, blending between the two either side. Where the slice column holds NAMES there is nothing to blend, so namedSliceOf selects the rows carrying the chosen name and namedStopsOf lists the names a control may offer.

#Functions

applicationLabel

What a key calls the reading a style attribute follows: #trial.status is "status", #self.degree "degree", a slider's letter its letter.

The map a style attribute's value applies last, folded or bound; null where it applies none.

The ramp a value ends in — #self.value -> -1..1 -> temperature — read off its last two steps; null where its last step is not a typed value of a type that applies (ramp).

The sizes a scale written -> lo..hi -> a + b_ (D71) runs between: the interval it normalised over, and the size its _ expression gives at each end — what a size key draws.

Returns a refined interval whose ends are already plain numbers, or null for anything else.

What a band is called in a key: 0 – 25, ≤ 0, < 0, ≥ 30, > 30, 0.

blendedItemColours

The same, blended item by item across an open !cue.to window: each end is resolved on its own and the two mixed.

boundColumnCells

Returns the cells of the column a binding names, or null when the value is not a column binding or the dataset's rows are not here.

buildSlicedSeries

Groups three parallel columns, a key, a slice and a value, into a series read at one slice, or returns null when any column does not resolve.

Returns what an axis calls the name at a 1-based position, in full — its label where the author gave one, else the name — or undefined where the position is off the axis.

categoryPosition

Returns the 1-based position a name takes on a categorical axis, or null where the axis has no such name.

Returns what each of an axis's ticks writes: a renamed name's label, else the tick — the short form for a preset, the name itself otherwise.

colourKeyEntries

The key entries a colour value's map earns: each key beside its colour, the map's otherwise as "other".

Returns the kind every non-blank cell of a column shares, or text when they do not share one.

columnParameterKindOf

Returns the number-line kind every non-blank cell of a column shares, or null if they do not all match one kind.

Parses a complex literal such as 4+2i, 2i+4, -i or 3.5j into its real and imaginary parts, or returns null for anything else.

datasetColumnKind

Returns how the column a binding names reads as a whole, or null when the value is not a column binding or the dataset has not arrived.

datasetParameterKind

Returns the kind a column holds for a parameter running over it, or null when its cells share no kind at all.

The footer line for the URL data a scene's environments draw, or null when they draw none.

Converts an ISO date to the fractional year it plots at, or returns null for anything else.

Returns the discrete numeric axis for a set of values: sorted ascending, duplicates dropped, each stop named by the number it is.

One end of an interval as a number: a plain number, or a tree over the scene's parameters — ..c — evaluated against their live values; NaN for an open end or one that cannot be read.

formatParameterValue

Formats a control's position back into a label for the reader, such as Mar, 09:30 or 2024-W12.

Returns the free identifiers of a refined expression: the single letters it uses that are neither built in nor its own variables.

intervalApplication

A value that applies a reading to a map of intervals and does nothing after — x -> (..8: solid; 8..: dashed), y * 2 -> (..<0: red; otherwise: teal) — as that reading and the intervals the map's keys span.

A compiled interval {from?, to?, from_exclusive?, to_exclusive?} as its ends.

isAxisPresetName

Returns whether a name is one of the AXIS_PRESETS, matched exactly in lower case.

isCategoricalAxis

Returns whether an axis is ruled in names.

Returns whether a value is a DateEntry.

isGeometryDataset

Returns whether a dataset is boundary geometry rather than a table.

Whether a dataset is filled from a URL (D74) rather than from an inline grid or an uploaded file.

Each item's colour from a colour style attribute.

Each item's fill style from a fill style attribute — solid, hatched or dotted — as itemStrokeStyles reads a stroke's.

An item's look as the scene's key draws it, for whatever else shows the item's colour — a tooltip's card.

A mark's opacity from its opacity style attribute: one number for the whole mark, or — from a list or an application — one per item, 0 to 1, with an item the value gives none drawn whole.

Each item's shape from a shape style attribute: one, a list cycled item by item, or one per item from an application.

Each item's size from a size or width style attribute, in the mark's own units: one for every item, a list cycled item by item, or one per item from an application — #self.degree -> 1..10 -> 1 + 2_ (D71).

itemStrokeStyles

Each item's stroke style from a stroke style attribute — solid, dashed or dotted — one for every item, a list cycled item by item, or one per item from an application; null where the value gives an item none, which draws in the mark's default.

Each item's value under a style attribute, as the compiler gives it: a name, a number, a colour literal, an { apply } a ramp finishes, or null where the value gives the item none.

Returns whether a kind's values are written as words or notation rather than as numbers: every kind but number.

The first colour a value names — what a mark's own label is written in: a written colour, or the first look of the map it applies.

One value's colour as CSS: a name or a literal through the palette, a ramp's { apply } finished at its place, fallback for anything else.

A map's entries as keys and looks, in written order and its otherwise last.

What a map entry's key reads as in a key: its name, its band, or "other" for the map's otherwise.

Returns the indices of the rows whose cell in a slice column of names equals a name, or null when the column does not resolve.

Returns the distinct names a column holds, in the order the rows first give them, which is what a categorical parameter's stops are read from.

parameterKindOfFormat

Returns the kind a written format: names, or null for auto, which is a deferral the caller decides from the data.

parameterValueOf

Converts a cell to the number a control positions it at: a date as a fractional year, a month as 1 to 12, and so on.

Parses CSV text into its header and rows, cells left as strings.

Reads a JSON response as a header and rows, by Chalk's mapping (spec 4.9, "JSON as rows").

Returns the categorical axis for a preset, with its short ticks.

resolveAttachedDatasets

Returns the document's datasets with every attached CSV's columns and rows filled in from the uploaded files.

Reads a boolean attribute that may be a condition, such as hidden: t > 3, at the current parameter values, or returns fallback.

resolveCategoricalColumn

Returns the column a binding names as positions on a categorical axis, or null if the value is not a column binding.

Returns the column a binding names as the strings the dataset holds, or null when the value is not a column binding or the dataset has not arrived.

resolveInterval

Evaluates an interval whose ends may be expressions, such as [0, 0.46 / s], at the current parameter values.

Evaluates a value that may be a number, an expression or a date to a number, at the current parameter values, or returns fallback.

resolveNumericColumn

Returns the column a binding names as numbers, or null if the value is not a column binding.

resolveSliceColumn

Returns a column a parameter runs over on its kind's number line, or null if the value is not a column binding.

Row indices 0..n-1, for items that stand one to a row.

Returns every key's value at one slice, interpolating between the two slices the reader stands between.

Returns the categorical axis for a written list of names, each tick writing its name.

Returns the first and last slice a series holds.

seriesEntryFreeVars

Returns the names of the parameters a series entry's expression depends on, or an empty list for an entry that is not an expression.

seriesEntryLabel

Returns the text label for a series entry, as a categorical axis would show it, or null for an entry that has none.

seriesEntryReading

Returns which reading a series entry offers an axis whose format is auto: a number, or a label.

Returns the distinct values a column holds on its number line, ascending, which is what a numeric parameter's range and natural stops are read from.

The colouring a value-reading mark's colour asks for.

Where one reading falls along a pinned window: its place, 0..1, clamped to the nearer end — clamp((x − lo) / (hi − lo), 0, 1), the compiler's rule for an interval applied to a number (D69), which a wash asks once per sample rather than once per item.

#Constants

The months and weekdays axes: full names with their three-letter ticks.

OTHERWISE_LABEL

What a key calls the readings a map's otherwise takes: one entry for them all, however many there are.

PARAMETER_FORMATS

The written vocabulary of a control's format:, in the order the documentation lists it.

#Interfaces

A ramp an application ends in: the ramp's name, and the window its reading was normalised over, if one was written.

The names a built-in categorical axis matches and the ticks it writes.

CategoricalAxis

An axis ruled in names.

A CSV's header and body, cells left as strings.

What a scene's footer says about the URL data its environments draw.

A date literal in a series or at a place on an axis: its text, and the year it plots at.

An interval key's ends, either absent for an open end, and whether each excludes its value (..<0, 0<..).

A span with both ends resolved to numbers.

Each item's colour, as CSS, and the key entries the value earns.

Each item's shape, and the key entries the value earns.

Each item's size, and the scale the value earns.

Where each item's readings come from.

ResolvedDataset

A dataset as the host resolved it: its rows filled in and, for a URL, when they were fetched.

A size scale's span and its drawn sizes at each end, for a key: the fields of a size footer scale but its kind and mark.

Long-format rows grouped for reading at one slice.

#Types

The uploaded text files an internote carries, by name.

A built-in categorical axis an author can name in an axis's format:: months or weekdays.

How a dataset column reads: numeric when every non-blank cell is a number, date when every one is an ISO date, complex when every one is a complex literal, and text otherwise.

What one entry of an applied map is keyed by: a name, an interval whose ends may follow a slider, or the map's otherwise (D62) — every reading no key holds.

The parameter kinds that have a number line: every kind but name.

ParameterFormat

What a control's format: may say: how the reader reads its values, or auto to decide from the bound data.

What kind of value a parameter holds, such as date, month or name, which decides how a control steps through it and labels it.

How a mark that reads a number of its own — a heatmap's cells, a choropleth's regions, a surface's height — is coloured, from its colour:

Last updated 26 September 2026

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