hadley / gg2v

Render ggplot2 graphics using vega

gg2v

A quick and dirty experiment exploring rendering ggplot2 graphics using vega.

This approach uses relatively little existing ggplot2 code, and the semantics may be slightly different. It is likely to converge over time as both vega and gg2v become more mature, but there's no expectation that ggplot2 and gg2v will ever be exactly concordances. It's probably easier to think of gg2v as an alternative specification and rendering of the graphics DSL defined by ggplot2.

Please note that this is an experimental prototype, and is unlikely to be maintained long-term (unless someone else volunteers).

Currently supported

• scales:
  • x and y position scales (continuous and categorical)
  • colour gradients
  • limited support for categorical colours
• geoms: point, line, path, area, text
• stats: none
• facets: none
• position adjustments: none

gg2v's Issues

column name missing in process_stats

Hey Hadley. I'm playing around with gg2v -- cool stuff. Actually planning to do some stuff with Vega in another language for work, but using gg2v to do some quick and dirty proof of concept work. I've found that some simple plots that work fine when rendered via ggplot break in gg2v, seemingly because column names aren't correctly set in aggregation. Here's an example:

> library(plyr)
> library(ggplot2)
> library(gg2v)
> data(baseball)
> p <- ggplot(baseball) + layer(mapping=aes_string(x='lg',y='r'), geom='bar', stat='summary', fun.y='sum')
> p                                 # this works
> gg2v(plot=p)                 # this doesn't
Error in eval(expr, envir, enclos) : object 'y' not found
> options(error=recover)
> gg2v(plot=p)
Error in eval(expr, envir, enclos) : object 'y' not found

Enter a frame number, or 0 to exit   

1: gg2v(plot = p)
2: plot_spec(plot, data_dir = data_dir, ...)
3: plot_data(plot)
4: Map(function(data, aes) render_data(data, aes, env = plot$plot_env), udata,
5: mapply(FUN = f, ..., SIMPLIFY = FALSE)
6: (function (data, aes) 
render_data(data, aes, env = plot$plot_env))(dots[[1]
7: render_data(data, aes, env = plot$plot_env)
8: eval(var, data, env)
9: eval(expr, envir, enclos)

Selection: 3
Called from: eval(var, data, env)
Browse[1]> head(data)
[[1]]
   x group     V1
1        1   2745
2 AA     2   9563
3 AL     3 299992
4 FL     4   1025
5 NL     5 373241
6 PL     6   2739
7 UA     7    300

Browse[1]> head(aes)
$f5f5faf07687c3b68ede8a16ee7e0bce
$f5f5faf07687c3b68ede8a16ee7e0bce$x
x

$f5f5faf07687c3b68ede8a16ee7e0bce$y
y

I'd like to get this fixed for my demos. The issue seems to be in plot-data.R::process_stats, but I'm not exactly sure what needs to be done. Any suggestions? Thanks!

-Harlan