R and ggplot: Trouble Labeling Stacked Bar Chart From Second Data Frame

Question

plot_data  <-  rbind(
                      data.frame(year = seq(2018,2027), value = seq(1000,10000,1000), type = 'Type A'),
                      data.frame(year = seq(2018,2027), value = seq(500,5000,500), type = 'Type B')
                      )
plot_labels     <-  data.frame(year = seq(2018,2027), label = seq(1500,15000,1500))

ggplot(plot_data, aes(x=as.character(year), y=value, fill=type)) +
geom_bar(width = .6, stat='identity') +
# geom_text(data = plot_labels, aes(x = year, y = text, label = label)) +
scale_x_discrete(name = '') +
scale_y_continuous(name = 'My Label\n') +
scale_fill_manual(name = '', values = c('red', 'blue')) +
theme(
  plot.title = element_text(size = 10, hjust = .5),
  panel.grid.major = element_line(colour = 'white', size = 1),
  panel.grid.minor = element_line(colour = 'white'),
  plot.background = element_rect(fill = 'white'),
  panel.background = element_rect(fill = 'white'),
  axis.text.x = element_text(colour = 'grey20', size = 7, angle = 45, hjust = 1),
  axis.title.y = element_text(color = 'grey20', size = 9),
  axis.text.y = element_text(colour = 'grey20', size = 7),
  legend.position='bottom',
  legend.key.size=unit(5,'mm'),
  legend.text = element_text(size = 7))

This code will produce a stacked bar chart.

My goal is to label this plot with plot_labels$label on the same y axis and scale as the stacked bar.

Uncommenting out line beginning with geom_text in plot definition throws the following error:

Error in eval(expr, envir, enclos) : object 'type' not found

plot_labels$label values are equivalent to summarizing plot_data$value by plot_data$year.

Would much appreciate the help in troubleshooting!

Answer 1

A few problems: 1) the fill should be placed in geom_bar, otherwise it will be inherited by all geoms that follow. 2) the geom_col is better than geom_bar when you provide both x and y. 3) in geom_text, x and y need to be the same type as in ggplot.

ggplot(plot_data, aes(x=as.character(year), y=value)) +
    geom_col(aes(fill=type), width = .6) +
    geom_text(data = plot_labels, aes(x = as.character(year), y = label, label = label), vjust = 0) +
    scale_x_discrete(name = '') +
    scale_y_continuous(name = 'My Label\n') +
    scale_fill_manual(name = '', values = c('red', 'blue')) +
    theme(
        plot.title = element_text(size = 10, hjust = .5),
        panel.grid.major = element_line(colour = 'white', size = 1),
        panel.grid.minor = element_line(colour = 'white'),
        plot.background = element_rect(fill = 'white'),
        panel.background = element_rect(fill = 'white'),
        axis.text.x = element_text(colour = 'grey20', size = 7, angle = 45, hjust = 1),
        axis.title.y = element_text(color = 'grey20', size = 9),
        axis.text.y = element_text(colour = 'grey20', size = 7),
        legend.position='bottom',
        legend.key.size=unit(5,'mm'),
        legend.text = element_text(size = 7))