ggplot stacked geom_bar - showing column values as label for bar

Question

With a dataframe df like below,

text <- "
MAKE,TIER,ENGINE_VENDOR,var,value
Maruti,HIGH,Fiat,miles,10424.5
Maruti,HIGH,Renault,miles,9784
Nissan,HIGH,Renault,miles,9616
Nissan,HIGH,Fiat,miles,9229
Tata,HIGH,Fiat,miles,9190
"
df <- read.table(textConnection(text), sep=",", header = T)

I want to create a stacked bar plot and add labels to each bar as value of the value column rounded to 0 decimals if > 100. So I do the following.

ggplot() +
    geom_bar(data=df, stat = "identity", position='dodge',
             aes(x=MAKE, y=value, fill=ENGINE_VENDOR, 
                 label = ifelse( value > 100, round(value,0), value)
             )
    ) + 
    geom_text(position = position_dodge(width = 1) )

This fails to give the labels in the plot. The plot generated is as below and gives Warning: Ignoring unknown aesthetics: label. I looked at the SO answer here for reference. How do I get the labels to be displayed for each bar, just below the top end of the bar and centered.

score 2 · Accepted Answer · answered Mar 23 '18 at 02:31

You can use tidyr::complete to complete missing factor levels (in your case the missing level in MAKE == "Tata").

I also would recommend performing any data manipulation such as generating labels prior to plotting. That you way you keep data manipulations and plotting separate.

require(tidyverse);
df %>%
    mutate(
        label = ifelse(value > 100, round(value, 0), value),
        ENGINE_VENDOR = factor(ENGINE_VENDOR)) %>%
    complete(MAKE, ENGINE_VENDOR) %>%
    ggplot(aes(MAKE, value, fill = ENGINE_VENDOR, label = label)) +
        geom_bar(stat = "identity", position = "dodge") +
        geom_text(position = position_dodge(width = 1))

ggplot stacked geom_bar - showing column values as label for bar

1 Answers1