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Plot - Terminal Charts in Rust

Rust crates.io License Platform Dependencies Stay Amazing

Render sparklines, line charts, candlestick charts, and bar charts directly in the terminal using Unicode block and braille characters with ANSI colors.

Pure Rust, zero dependencies. All chart types produce plain strings with embedded ANSI codes, composable with any TUI framework.

Feature clone of termchart.

Quick Start

Add to your Cargo.toml:

[dependencies]
plot = { version = "0.1", path = "../plot" }
use plot::{spark, Bar, Orientation, Line, Candle, Color};
// Sparkline
println!("{}", spark(&[1.0, 3.0, 7.0, 2.0, 5.0, 8.0], Some(82)));
// Output: ▁▃█▂▅█ (in green)

Chart Types

Sparklines

Compact single-line visualization using eighth-block characters (\u{2581}\u{2582}\u{2583}\u{2584}\u{2585}\u{2586}\u{2587}\u{2588}).

use plot::spark;
let s = spark(&[1.0, 4.0, 7.0, 2.0, 8.0, 3.0, 6.0, 9.0, 5.0], Some(82));
println!("{}", s);
// ▁▃▆▂█▃▅█▄
  • 8 levels of vertical resolution
  • Optional 256-color
  • Handles empty data and flat values (all same)

Bar Charts

Horizontal and vertical bars with sub-cell 1/8th precision.

use plot::{Bar, Orientation};
// Horizontal
let mut bar = Bar::new(50, Orientation::Horizontal);
bar.add("Rust",   95.0, Some(208));
bar.add("Go",     78.0, Some(81));
bar.add("Python", 85.0, Some(226));
bar.add("Ruby",   72.0, Some(196));
println!("{}", bar.render());
  Rust \u{2502}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}  95
    Go \u{2502}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{258E}        78
Python \u{2502}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}      85
  Ruby \u{2502}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{2588}\u{258A}           72

// Vertical
let mut vbar = Bar::new(30, Orientation::Vertical);
vbar.set_height(10);
vbar.add("Q1", 80.0, Some(82));
vbar.add("Q2", 95.0, Some(82));
vbar.add("Q3", 60.0, Some(196));
vbar.add("Q4", 110.0, Some(82));
println!("{}", vbar.render());

Line Charts

High-resolution braille dot plotting (2x4 dots per character cell) with Y-axis labels and multi-series legend.

use plot::Line;
let mut chart = Line::new(60, 15);
chart.add(&[10.0, 15.0, 12.0, 20.0, 18.0, 25.0, 22.0, 30.0], 82, Some("Price"));
chart.add(&[5.0, 8.0, 10.0, 7.0, 12.0, 9.0, 15.0, 11.0], 226, Some("Volume"));
println!("{}", chart.render());
  • Braille characters (U+2800-U+28FF) for 2x resolution horizontally, 4x vertically
  • Bresenham line algorithm for smooth connections
  • Y-axis with min/mid/max labels
  • Multi-series support with colored legend

Candlestick Charts

OHLC (Open-High-Low-Close) financial charts with green (up) and red (down) candles.

use plot::Candle;
use plot::candle::OhlcBar;
let mut chart = Candle::new(50, 15);
chart.add(&[
    OhlcBar { o: 100.0, h: 105.0, l: 98.0,  c: 103.0 },
    OhlcBar { o: 103.0, h: 107.0, l: 101.0, c: 99.0  },
    OhlcBar { o: 99.0,  h: 104.0, l: 97.0,  c: 102.0 },
    OhlcBar { o: 102.0, h: 110.0, l: 100.0, c: 108.0 },
]);
println!("{}", chart.render());
  • Wicks: \u{2502} (thin vertical)
  • Bodies: \u{2588} (full block) for range, \u{2500} (horizontal line) for doji
  • Green (82) for up candles, Red (196) for down
  • Y-axis with 5 price levels
  • Auto-limits visible candles to fit chart width

Color Support

use plot::Color;
// 256-color palette (0-255)
let c = Color::Index(82); // green
// RGB hex
let c = Color::from_str("#FF0000").unwrap(); // red RGB
let c = Color::from_str("00FF00").unwrap();  // green RGB
// Named colors (matching termchart)
let c = Color::from_str("red").unwrap();     // → Index(196)
let c = Color::from_str("green").unwrap();   // → Index(82)
let c = Color::from_str("blue").unwrap();    // → Index(33)
let c = Color::from_str("yellow").unwrap();  // → Index(226)
let c = Color::from_str("cyan").unwrap();    // → Index(51)
let c = Color::from_str("magenta").unwrap(); // → Index(201)
let c = Color::from_str("white").unwrap();   // → Index(255)
let c = Color::from_str("gray").unwrap();    // → Index(245)
let c = Color::from_str("orange").unwrap();  // → Index(208)

Canvas API

For custom chart types, use the Canvas and BrailleCanvas directly:

use plot::{Canvas, BrailleCanvas};
// Simple character canvas
let mut c = Canvas::new(20, 5);
c.set(0, 0, "#", Some(196), None);  // red '#' at top-left
println!("{}", c.render());
// High-resolution braille canvas
let mut bc = BrailleCanvas::new(40, 10);
// Resolution: 80x40 pixels (2x4 dots per character)
bc.set_dot(10, 5, Some(82));  // green dot at pixel (10,5)
println!("{}", bc.render());

API Reference

Type Constructor Methods
spark() spark(values, color) Returns String
spark_color() spark_color(values, color) Color enum variant
Bar Bar::new(width, orientation) add(label, value, color), set_height(h), render()
Line Line::new(width, height) add(values, color, label), render()
Candle Candle::new(width, height) add(bars), render()
Canvas Canvas::new(w, h) set(x,y,ch,fg,bg), get(x,y), render()
BrailleCanvas BrailleCanvas::new(w, h) set_dot(px,py,fg), px_width(), px_height(), render()
Color Color::Index(u8), Color::Rgb(r,g,b) from_str(s), fg_code(), bg_code()

Unicode Characters Used

Chart Characters Description
Sparkline \u{2581}\u{2582}\u{2583}\u{2584}\u{2585}\u{2586}\u{2587}\u{2588} Eighth-height blocks (8 levels)
Bar (H) \u{258F}\u{258E}\u{258D}\u{258C}\u{258B}\u{258A}\u{2589}\u{2588} Eighth-width blocks (8 levels)
Bar (V) \u{2581}\u{2582}\u{2583}\u{2584}\u{2585}\u{2586}\u{2587}\u{2588} Eighth-height blocks (8 levels)
Line U+2800-U+28FF Braille patterns (2x4 dots per cell)
Candle \u{2502} \u{2500} \u{2588} Wick, doji, body
Y-axis \u{2524} \u{2502} Label marker, vertical line
Tool Clones Type
rush rsh Shell
crust rcurses TUI library
glow termpix Image display
plot termchart Charts
pointer RTFM File manager
kastrup Heathrow Messaging
tock Timely Calendar
scroll brrowser Browser

License

Unlicense - public domain.

Credits

Created by Geir Isene (https://isene.org) with extensive pair-programming with Claude Code.

Read the original on github.com ↗