Skribilo contains a pie-chart formatting package, located in the (skribilo package pie) module. It allows users to produces represent numeric data as pie charts as in the following example:

Use of Document Formatting Systems

A default implementation, which uses Ploticus as an external program, is available for all engines. There is also a specific implementation for the Lout engine which relies on Lout's own pie-chart package. In the latter case, you don't need to have Ploticus installed, but you need it in the former.

Currently it only supports slice-coloring, but support for textures (particularly useful for black & white printouts) could be added in the future.

Let us start with a simple example:

;; A sad pie chart. ;; (pie :title [Casualties in the Israel-Lebanon 2006 Conflict (source: English Wikipedia page, 2006-07-23)] :total 450 ;; to show the uncertainty on figures :ident "pie-lebanon-2006" :labels 'outside :fingers? #t (slice :weight 8 :color "black" [Hezbollah militants]) (slice :weight 42 :color "blue" [soldiers]) (slice :weight 317 :color "red" :detach? #t [civilians (,(sliceweight :percentage? #t)%)]))

Ex. 38: Example of a pie chart

... produces:

Casualties in the Israel-Lebanon 2006 Conflict (source: English Wikipedia page, 2006-07-23)

This illustrates the three markups provided by the pie package, namely pie, slice, and sliceweight. This last markup returns the weight of the slice it is used in, be it as a percentage or an absolute value. Note that the :total option of pie can be used to create pie charts no entirely filled.

Various options allow the pie layout to be controlled:

;; Another sad pie chart. ;; (pie :title [Casualties of the Conflict in Iraq since 2003 (source: English Wikipedia page, 2006-07-23)] :ident "pie-iraq-2006" :fingers? #f :labels 'inside :initial-angle 45 :radius 2 (slice :weight 100000 :color "red" :detach? #t [civilians (,(sliceweight :percentage? #t)%)]) (slice :weight (+ 2555 229) :color #xeeeeee [soldiers]))

Ex. 39: Specifying the layout of a pie chart

... produces:

Casualties of the Conflict in Iraq since 2003 (source: English Wikipedia page, 2006-07-23)