4.20 Axes

• We can modify axes/scales using various functions as depicted in Figure 4.9.
• xlab() and ylab(): Set labels
• scale_color_manual(): Manually set the color scale (same logic for other scales)
• scale_x_continuous(): Manually set a numeric scale
• xlim() and ylim(): Set limits

# data_twitter_influence.csv
data <- read_csv(sprintf("https://docs.google.com/uc?id=%s&export=download",
                                "1dLSTUJ5KA-BmAdS-CHmmxzqDFm2xVfv6"),
                        col_types = cols())
ggplot(data %>% filter(followers_count<50000), 
       aes(x = account_age_years, 
           y = followers_count, 
           color = factor(female))) + 
           geom_point(alpha =0.5) + 
           facet_wrap(~party) +
  ylab("Number of followers") +
  xlab("Account age (in years)") +
  scale_colour_manual(name = "Gender",
                     values = c("0" = "pink", "1" = "blue"),
                     labels = c("0" = "male", "1" = "female")) +
  scale_x_continuous(breaks = c(0, 5, 10), limits = c(0,10)) +
  xlim(0,5) # Replaces x-scale characteristics before

## Scale for 'x' is already present. Adding another scale for 'x', which will
## replace the existing scale.

## Warning: Removed 302 rows containing missing values (geom_point).

Figure 4.9: Modifying scales and axes