Tetley caffeine meter replication with ggplot2
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Tetley tea boxes feature the following caffeine meter:

In R we can replicate this meter using ggplot2.
Move the information to a tibble:
library(dplyr)
caffeine_meter <- tibble(
cup = c("Coffee", "Tea", "Green Tea", "Decaf Tea"),
caffeine = c(99, 34, 34, 4)
)
caffeine_meter
# A tibble: 4 × 2 cup caffeine <chr> <dbl> 1 Coffee 99 2 Tea 34 3 Green Tea 34 4 Decaf Tea 4
Now we can plot the caffeine meter using ggplot2:
library(ggplot2) g <- ggplot(caffeine_meter) + geom_col(aes(x = cup, y = caffeine, fill = cup)) g

Then I add the colours that I extracted with GIMP:
pal <- c("#f444b3", "#3004c9", "#85d26a", "#3a5dff")
g + scale_fill_manual(values = pal)

The Decaf Tea category should be at the end of the plot, so I need to transform the “cup” column to a factor sorted decreasingly by the “caffeine” column:
library(forcats) caffeine_meter <- caffeine_meter %>% mutate(cup = fct_reorder(cup, -caffeine)) g <- ggplot(caffeine_meter) + geom_col(aes(x = cup, y = caffeine, fill = cup)) + scale_fill_manual(values = pal) g

Now I can change the background colour to a more blueish gray:
g + theme(panel.background = element_rect(fill = "#dcecfc"))

Now I need to add the title with a blue background, so putting all together:
caffeine_meter <- caffeine_meter %>%
mutate(title = "Caffeine Meter\nIf brewed 3-5 minutes")
ggplot(caffeine_meter) +
geom_col(aes(x = cup, y = caffeine, fill = cup)) +
scale_fill_manual(values = pal) +
facet_grid(. ~ title) +
theme(
strip.background = element_rect(fill = "#3304dc"),
strip.text = element_text(size = 20, colour = "white", face = "bold"),
panel.background = element_rect(fill = "#dcecfc"),
legend.position = "none"
)

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