ggplot 0.5.7
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New geoms, scales and aesthetics

  * stat_step and geom_step to draw staircase plots (like plot(type="s"))
  * order aesthetic (currently only for lines/paths) allows you to control the drawing order within a group
  * scale_manual makes it easier to let ggplot uses the exact colours/sizes/linetypes that you want
  * scale_reverse allows you to reverse the scale of x and y axes
  * scale_grey is a new black and white scale for categorical data (colour and fill)


Improved options handling

  * new function opts() to allow modification of plot options by addition
  * update(p, theme_bw) and p + theme_bw now work

These changes mean that you can modify plot options in the same way that you modify all other aspects of the plot, e.g.  qplot(mpg, wt, data=mptcars) + opts(title = "Fuel economy vs weight")

Improved documentation

  * many tweaks to the online documentation, particular including the actual code you need to run for each object!
  * every page now has a link to a form where you can submit feedback on exactly you do or don't like about a page
  * required aesthetics now listed in documentation
  * geom_polygon now has a decent example
  * numerous minor corrections suggested by Jörg Beyer
  * separated plotting advice from details of plot construction (what vs how), thanks to Bert Gunter for this suggestion


Improved map projections (with coord_map)

  * coord_map defaults to orientation = c(90, 0, mean(range(y))) - this ensures that multiple layers line up correctly, but means you will have to specify the orientation yourself for many projections 
  * coord_map now respects limits set by scales
  * removed useless ticks from coord_map

If you're using ggplot to draw maps and have thought of other features that would make your life easier, please let me know.


Bug fixes

  * adding data and aesthetics in separate steps should now work
  * layers with set parameters will not use mapped aesthetics
  * use LazyLoad: false instead of SaveData: true for better future compatability

  * coord_cartesian: fixed bug that prevented you from overriding the default axis expansion
  * coord_equal: now scales correctly if ratio < 1
  * geom_abline: fix bug where slope was ignored
  * geom_jitter now works correctly with groups and categorical values (was actually a bug in how scale_discrete deals with continuous values)
  * geom_path: automatically switch between polylineGrob and segmentsGrob when drawing paths so that setting line type now works properly
  * geom_segment now uses both ends of segments to calculate axis limits
  * plotmatrix: fix bug in scatterplot matrix where all scatterplots were transposed!
  * qplot: should now work better within functions
  * quickplot added as an alias of qplot, to avoid confusion with qunif, etc
  * scale_*: better error message if you add a scale without a matching aesthetic mapping in the plot
  * scale_identity no longer converts everything to character
  * scale_identity: grob argument renamed to guide
  * stat_*: made all statistics more robust to errors
  * stat_quantile: fixed bug when only drawing a single quantile
  * stat_smooth: returns silently if <2 non-missing data points


Minor aesthetic improvements

  * coord_polar now specifies aspect.ratio by default, and I've made a few other tweaks to make polar coordinates plot look nicer
  * geom_bar no longer draws gray borders by default, but instead uses the same colour as fill (this eliminates a tiny gap between neighbouring bars)
  * plotmatrix: tweaks to improve display of scatterplot matrix
  * scale_brewer: added option to reverse palette
  * scale_colour: colour and fill legends now look exactly the same (previously colour was missing a grey border)
  * scale_discrete has slightly larger expansion (0.75 vs 0.5)
  * stat_bar: only output bars with > 0 count


See CHANGELOG for changes in previous versions