ggplot2 code for generating grid plots for proportional comparison

chiclet_plot.r

# Generate test data
chicdat <- diamonds

# calculate percentages by the categorical variable
chicdat$pct.full <- 1/nrow(chicdat)
catpct <- ddply(chicdat, .(cut), summarize, pct=sum(pct.full))
catpct$rollpct <- cumsum(catpct$pct)




# Box Precision: what's the smallest portion that each box represents?
# A 400-box grid can show 0.25%, for example, so 400 boxes is the default
boxcount <- 400
boxcols  <- 10
boxrows <- boxcount / boxcols
boxes <- expand.grid(boxcol = seq(1:boxcols), boxrow=seq(1:boxrows) )
boxes$boxpct <- 1/boxcount
boxes$boxbottom <- cumsum(boxes$boxpct) - boxes$boxpct
boxes$boxtop <- cumsum(boxes$boxpct)


ddply(chicdat, .(cut), summarize, sum(pct.full))

boxes$boxcat <- cut(boxes$boxbottom, c(-0.01, catpct$rollpct), catpct$cut)

# Plot the graph
ggplot(boxes) + geom_tile(aes(x=boxcol, y=boxrow, fill=boxcat) ,color='white') + 
  theme(
  plot.background = element_blank()
  ,panel.grid.major = element_blank()
  ,panel.grid.minor = element_blank()
  ,panel.border = element_blank()
 # ,panel.background = element_blank()
  ,axis.ticks = element_blank()
  ,axis.text = element_blank()
  ,axis.title = element_blank()
) +
  scale_x_continuous(expand = c(0,0)) + 
  scale_y_reverse(expand = c(0,0)) + 
  coord_fixed(ratio = 1) +
  scale_fill_brewer(type='qual') + 
  guides(fill = guide_legend(title='Category'))