# markvis

Write a table of numbers in a Markdown code block tagged `chart`, `markvis`, or `vis`. That block is the chart. Same text, same picture. If it cannot draw, keep the table.

Fetch this file. Emit that code block. Do not invent fields.

## Fence (the code block)

Tags `chart`, `markvis`, and `vis` are the same language.

Order:

1. Optional `markvis: 2`
2. One `key: value` per line
3. Blank line
4. Data: CSV, or one GFM table

Fields:

- `type` required. Only `bar` `line` `area` `scatter` `pie` `hist`.
- `title` optional. A conclusion, not a slug.
- `theme` optional. Omit means `folio`. Allowed: `folio` `highcharts` `shadcn` `docs` `ant` `recharts`. Any other value is `E_UNKNOWN_THEME`: show the table, not a silent swap.
- `palette` optional. Colors only. Allowed: `ink` `porcelain` `warm` `cool` `vivid`. Omit means the theme’s default colors. Any other value is `E_UNKNOWN_PALETTE`: show the table, not a silent swap. Never merge palette into the theme id.
- `unit` optional.
- `x` `y` `series` name real columns. `series` splits series.
- Data required. Not JSON.

Also valid: an HTML comment immediately followed by a GFM table.

`<!-- chart: bar x=month y=tickets title="Mar led Midtown box office at 9.2k tickets" -->`

Comment keys: `type` (required), `x`, `y`, `title`, `unit`, `series`, `theme`, `palette`. Same meaning as fence headers.

## Types

- `bar` — category x, number y. Keep row order. Do not sort.
- `line` — ordered x, number y. Optional `series`. Keep row order.
- `area` — same as line, filled.
- `scatter` — number x, number y. One mark per row.
- `pie` — label x, number y >= 0. Do not force the slices to 100.
- `hist` — number x. Table keeps the raw rows.

On any error: keep the rows, show the table, add one line with the error code. Never drop the numbers.

## Copy these

### Bar

```chart
markvis: 2
type: bar
title: Mar led Midtown box office at 9.2k tickets
unit: tickets
x: month
y: tickets

month,tickets
Sep,5200
Oct,6100
Nov,7800
Dec,8500
Jan,4800
Feb,7200
Mar,9200
Apr,6900
```

### Line

```chart
type: line
title: Walk-up still leads member through week 12
x: week
y: count
series: channel

week,channel,count
W1,walk-up,64
W1,member,28
W2,walk-up,68
W2,member,32
W3,walk-up,71
W3,member,35
W4,walk-up,69
W4,member,38
W5,walk-up,74
W5,member,41
W6,walk-up,72
W6,member,44
W7,walk-up,75
W7,member,47
W8,walk-up,73
W8,member,50
W9,walk-up,76
W9,member,53
W10,walk-up,74
W10,member,55
W11,walk-up,77
W11,member,57
W12,walk-up,78
W12,member,59
```

### Pie

```markvis
type: pie
title: MARTA takes the largest mode share
x: mode
y: count

mode,count
MARTA,38
Walk,24
Drive,22
Bike,11
Other,8
```

Emit the fence. Do not emit a PNG. Do not add a seventh type.