Copyright	(c) 2025
License	MIT
Maintainer	mschavinda@gmail.com
Stability	experimental
Portability	POSIX
Safe Haskell	None
Language	GHC2021

Granite

Contents

Plot Configuration
Data Preparation
Chart Types

Description

A terminal-based plotting library that renders beautiful charts using Unicode Braille characters and ANSI colors. Granite provides a variety of chart types including scatter plots, line graphs, bar charts, pie charts, histograms, heatmaps, and box plots.

Basic Usage

Create a simple scatter plot:

{-# LANGUAGE OverloadedStrings #-}
import Granite
import Data.Text.IO as T

main = do
  let points = [(x, sin x) | x <- [0, 0.1 .. 6.28]]
      chart = scatter [series "sin(x)" points] defPlot
  T.putStrLn chart

Customization

Plots can be customized using record update syntax:

let customPlot = defPlot 
      { widthChars = 80
      , heightChars = 30
      , plotTitle = "My Chart"
      , legendPos = LegendBottom
      }

Terminal Requirements

This library requires a terminal that supports:

Unicode (specifically Braille patterns U+2800-U+28FF)
ANSI color codes
Monospace font with proper Braille character rendering

Synopsis

data Plot = Plot {
- widthChars :: Int
- heightChars :: Int
- leftMargin :: Int
- bottomMargin :: Int
- titleMargin :: Int
- xBounds :: (Maybe Double, Maybe Double)
- yBounds :: (Maybe Double, Maybe Double)
- plotTitle :: Text
- legendPos :: LegendPos
}
defPlot :: Plot
data LegendPos
- = LegendRight
- | LegendBottom
series :: Text -> [(Double, Double)] -> (Text, [(Double, Double)])
bins :: Int -> Double -> Double -> Bins
histogram :: Bins -> [Double] -> Plot -> Text
bars :: [(Text, Double)] -> Plot -> Text
scatter :: [(Text, [(Double, Double)])] -> Plot -> Text
pie :: [(Text, Double)] -> Plot -> Text
stackedBars :: [(Text, [(Text, Double)])] -> Plot -> Text
heatmap :: [[Double]] -> Plot -> Text
lineGraph :: [(Text, [(Double, Double)])] -> Plot -> Text
boxPlot :: [(Text, [Double])] -> Plot -> Text

Plot Configuration

data Plot Source #

Plot configuration parameters.

Controls the appearance and layout of generated charts.

Constructors

Plot

Fields

widthChars :: Int
Width of the plot area in terminal characters (default: 60)
heightChars :: Int
Height of the plot area in terminal characters (default: 20)
leftMargin :: Int
Space reserved for y-axis labels (default: 6)
bottomMargin :: Int
Space reserved for x-axis labels (default: 2)
titleMargin :: Int
Space above the plot for the title (default: 1)
xBounds :: (Maybe Double, Maybe Double)
Optional manual x-axis bounds (min, max). Nothing uses automatic bounds with 5% padding.
yBounds :: (Maybe Double, Maybe Double)
Optional manual y-axis bounds (min, max). Nothing uses automatic bounds with 5% padding.
plotTitle :: Text
Title displayed above the plot (default: empty)
legendPos :: LegendPos
Position of the legend (default: LegendRight)

Instances

Instances details

Show Plot Source #
Instance details Defined in Granite Methods showsPrec :: Int -> Plot -> ShowS # show :: Plot -> String # showList :: [Plot] -> ShowS #
Eq Plot Source #
Instance details Defined in Granite Methods (==) :: Plot -> Plot -> Bool # (/=) :: Plot -> Plot -> Bool #

defPlot :: Plot Source #

Default plot configuration.

Creates a 60×20 character plot with reasonable defaults:

defPlot = Plot
  { widthChars   = 60
  , heightChars  = 20
  , leftMargin   = 6
  , bottomMargin = 2
  , titleMargin  = 1
  , xBounds      = (Nothing, Nothing)
  , yBounds      = (Nothing, Nothing)
  , plotTitle    = ""
  , legendPos    = LegendRight
  }

data LegendPos Source #

Position of the legend in the plot.

Constructors

LegendRight	Display legend on the right side of the plot
LegendBottom	Display legend below the plot

Instances

Instances details

Show LegendPos Source #
Instance details Defined in Granite Methods showsPrec :: Int -> LegendPos -> ShowS # show :: LegendPos -> String # showList :: [LegendPos] -> ShowS #
Eq LegendPos Source #
Instance details Defined in Granite Methods (==) :: LegendPos -> LegendPos -> Bool # (/=) :: LegendPos -> LegendPos -> Bool #

Data Preparation

series Source #

Arguments

:: Text	Name of the series (appears in legend)
-> [(Double, Double)]	List of (x, y) data points
-> (Text, [(Double, Double)])

Create a named data series for multi-series plots.

let s1 = series "Dataset A" [(1,2), (2,4), (3,6)]
    s2 = series "Dataset B" [(1,3), (2,5), (3,7)]
    chart = scatter [s1, s2] defPlot

bins :: Int -> Double -> Double -> Bins Source #

Create a bin configuration for histograms.

bins 10 0 100  -- 10 bins from 0 to 100
bins 20 (-5) 5 -- 20 bins from -5 to 5

Chart Types

histogram Source #

Arguments

:: Bins	Binning configuration
-> [Double]	Raw data values to bin
-> Plot	Plot configuration
-> Text	Rendered chart as Text

Create a histogram from numerical data.

Data is binned according to the provided Bins configuration.

Example

Expand

import System.Random

-- Generate random normal-like distribution
let values = take 1000 $ randomRs (0, 100) gen
    chart = histogram (bins 20 0 100) values defPlot

bars Source #

Arguments

:: [(Text, Double)]	List of (category, value) pairs
-> Plot	Plot configuration
-> Text	Rendered chart as Text

Create a bar chart from categorical data.

Each bar is colored differently and labeled with its category name.

Example

Expand

let data = [(Apple, 45.2), (Banana, 38.1), (Orange, 52.7)]
    chart = bars data defPlot { plotTitle = "Fruit Sales" }

scatter Source #

Arguments

:: [(Text, [(Double, Double)])]	List of named data series
-> Plot	Plot configuration
-> Text	Rendered chart as Text

Create a scatter plot from multiple data series.

Each series is rendered with a different color and pattern. Points are plotted using Braille characters for sub-character resolution.

Example

Expand

let points1 = [(x, x^2) | x <- [-3, -2.5 .. 3]]
    points2 = [(x, 2*x + 1) | x <- [-3, -2.5 .. 3]]
    chart = scatter [series "y = x²" points1, 
                     series "y = 2x + 1" points2] defPlot

pie Source #

Arguments

:: [(Text, Double)]	List of (category, value) pairs
-> Plot	Plot configuration
-> Text	Rendered chart as Text

Create a pie chart showing proportions.

Values are normalized to sum to 100%. Negative values are treated as zero.

Example

Expand

let data = [(Chrome, 65), (Firefox, 20), (Safari, 10), (Other, 5)]
    chart = pie data defPlot { plotTitle = "Browser Market Share" }

stackedBars Source #

Arguments

:: [(Text, [(Text, Double)])]	Categories with stacked components
-> Plot	Plot configuration
-> Text	Rendered chart as Text

Create a stacked bar chart.

Each category can have multiple stacked components.

Example

Expand

let data = [(Q1, [("Product A", 100), ("Product B", 150)]),
            (Q2, [("Product A", 120), ("Product B", 180)])]
    chart = stackedBars data defPlot

heatmap Source #

Arguments

:: [[Double]]	2D matrix of values (rows × columns)
-> Plot	Plot configuration
-> Text	Rendered chart as Text

Create a heatmap visualization of a 2D matrix.

Values are mapped to a color gradient from blue (low) to red (high).

Example

Expand

let matrix = [[x * y | x <- [1..10]] | y <- [1..10]]
    chart = heatmap matrix defPlot { plotTitle = "Multiplication Table" }

lineGraph Source #

Arguments

:: [(Text, [(Double, Double)])]	List of named data series
-> Plot	Plot configuration
-> Text	Rendered chart as Text

Create a line graph connecting data points.

Similar to scatter but connects consecutive points with lines. Points are automatically sorted by x-coordinate before connecting.

Example

Expand

let sine = [(x, sin x) | x <- [0, 0.1 .. 2*pi]]
    cosine = [(x, cos x) | x <- [0, 0.1 .. 2*pi]]
    chart = lineGraph [series "sin" sine, series "cos" cosine] defPlot

boxPlot Source #

Arguments

:: [(Text, [Double])]	Named datasets
-> Plot	Plot configuration
-> Text	Rendered chart as Text

Create a box plot showing statistical distributions.

Displays quartiles, median, and min/max values for each dataset.

Example

Expand

let data1 = [1.2, 2.3, 2.1, 3.4, 2.8, 4.1, 3.9]
    data2 = [5.1, 4.8, 6.2, 5.9, 7.1, 6.5, 5.5]
    chart = boxPlot [("Group A", data1), ("Group B", data2)] defPlot

The box plot displays:

Box: First quartile (Q1) to third quartile (Q3)
Line inside box: Median (Q2)
Whiskers: Minimum and maximum values