# Enum: MarkType 




_The cartesian primitive a grammar layer draws (heatmap is implied by a heatmap panel, not a mark)._



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URI: [tvbo:enum/MarkType](https://w3id.org/tvbo/enum/MarkType)

## Permissible Values
| Value | Meaning | Description |
| --- | --- | --- |
| line | None | Connected line (timeseries, bifurcation branch, trajectory) |
| scatter | None | Points (fixed points, special points, per-node profiles) |
| rule | None | Reference line at a value the layer's output HOLDS (a threshold, a published ... |
| band | None | Filled band between two series (an error band, a CI) |
| area | None | Series filled down to the baseline (a density/pdf, a cumulative share) |
| bar | None | Vertical bars, one per x (spectrum, per-category magnitude) |




## Slots

| Name | Description |
| ---  | --- |
| [mark](../slots/mark.qmd) | Cartesian mark; omitted for heatmap panels (implied by the panel kind) |










## Identifier and Mapping Information





### Schema Source


* from schema: https://w3id.org/tvbo/figure






## LinkML Source

<details>
```yaml
name: MarkType
description: The cartesian primitive a grammar layer draws (heatmap is implied by
  a heatmap panel, not a mark).
from_schema: https://w3id.org/tvbo/figure
permissible_values:
  line:
    text: line
    description: Connected line (timeseries, bifurcation branch, trajectory).
  scatter:
    text: scatter
    description: Points (fixed points, special points, per-node profiles).
  rule:
    text: rule
    description: 'Reference line at a value the layer''s output HOLDS (a threshold,
      a published number, an ensemble mean) — one line per value. The encoded channel
      picks the orientation: `x:` draws vertical, `y:` horizontal. Distinct from the
      `axvline`/`axhline` opts, which take a literal typed into the spec and are drawn
      as subdued gridlines.'
  band:
    text: band
    description: Filled band between two series (an error band, a CI). Its layer's
      output carries a length-2 axis beside the swept one, holding the two edges in
      ONE array — binding a lower edge and an upper edge as separate layers lets them
      come from different runs.
  area:
    text: area
    description: Series filled down to the baseline (a density/pdf, a cumulative share).
      Distinct from `band`, which spans two series, and from `bar`, which asserts
      the x values are discrete categories.
  bar:
    text: bar
    description: Vertical bars, one per x (spectrum, per-category magnitude). Distinct
      from `line` because a spectrum read as a line implies interpolation between
      mode numbers that do not exist.

```
</details>

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