Graphics.Google.Chart

This module is for generating web-based charts using Google's Chart API: http://code.google.com/apis/chart/. Its output is URLs that will resolve to a PNG image of the resulting chart.

Most of the functions in this module, with names like setFoo, take a Chart as an argument and produce a new Chart with the specified attribute added. These calls are designed to be chained together. See the example below.

Charts are represented as a hierarchy of type classes so that parameters that only affect a specific chart type are only available to that chart type.

putStrLn "URL for your chart:"
putStrLn $ chartURL $
  setSize 400 257 $
  setTitle "My Chart" $
  setData (encodeDataSimple [[1..20]]) $
  setLegend ["1 to 20"] $
  newLineChart

This produces: http://chart.apis.google.com/chart?chs=400x257&chtt=My+Chart&chd=s%3aBCDEFGHIJKLMNOPQRSTU&chdl=1+to+20&cht=lc

Chart basics

These functions and types are shared by all chart types.

class Chart c

The type class underneath all Charts.

Instances

Chart BarChart

Chart PieChart

Chart LineChart

chartURL :: Chart c => c -> String

Construct the URL used to show the chart.

setSize :: Chart c => Int -> Int -> c -> c

Set the width and height, in pixels, of the resulting image.

setTitle :: Chart c => String -> c -> c

Set the title of the chart.

setTitleOpts

Arguments

:: Chart c

=> String

Color of the text.

-> Int

Size of the text.

-> c

-> c

Set options for the display of the title of the chart.

setData :: Chart c => ChartData -> c -> c

Set the data displayed by the chart.

Chart data

There are multiple options for encoding chart data. See http://code.google.com/apis/chart/#chart_data for more details.

data ChartData

All the encoding methods produce ChartData, which is usable by setData.

Instances

Show ChartData

encodeDataSimple :: [[Int]] -> ChartData

Encode data using the "simple" encoding. This produces minimal URLs but doesn't have as much resolution. Input values must be in the range 0 <= x <= 61. Values outside the valid input range will be considered missing data.

encodeDataText :: [[Int]] -> ChartData

Encode data using the "text" encoding. XXX unimplemented.

encodeDataExtended :: [[Int]] -> ChartData

Encode data using the "extended" encoding. XXX unimplemented.

Chart features

class Chart c => LegendChart c where

LegendChart represents charts that can display legends with setLegend.

Methods

setLegend :: [String] -> c -> c

Set the legend for the corresponding data sets. The colors are taken from the data set colors.

Instances

LegendChart BarChart

LegendChart LineChart

Specific chart types

Line charts

data LineChart

Instances

LegendChart LineChart

Chart LineChart

newLineChart :: LineChart

Pie charts

data PieChart

Instances

Chart PieChart

newPieChart :: PieStyle -> PieChart

data PieStyle

Constructors

Pie2D

Pie3D

setLabels :: [String] -> PieChart -> PieChart

Bar charts

data BarChart

Instances

LegendChart BarChart

Chart BarChart

newBarChart :: Orientation -> BarStyle -> BarChart

data Orientation

Constructors

Horizontal

Vertical

data BarStyle

Constructors

Stacked

Grouped