ScalesGuidesThemes.R

#------------------------------------------------------------------------------#
# Working with scales, guides and themes
# Mango Solutions - EARL Workshop
#------------------------------------------------------------------------------#

library(tidyverse)
library(forcats)

funded <- read_csv("http://bit.ly/UKFundedSports0016")

basicPlot <- ggplot(data = mutate(funded, 
    SportGroup = fct_reorder(SportGroup, -Funding), 
    Location = fct_reorder(Location, Year))) +
  geom_bar(aes(
      x = Location, 
      y = Funding, 
      fill = SportGroup), 
    stat = "summary", 
    fun.y = "sum")

basicPlot


#------------------------------------------------------------------------------#
# Setting Labels
#------------------------------------------------------------------------------#

labelPlot <- basicPlot +
  labs(
    title = "Changes in Funding For Olympic Sports",
    subtitle = "Funding Provided by UK Sport World Class Performance Programme",
    x = "", y = "", 
    caption = "Data taken from uksport.gov.uk",
    fill = "Event")

labelPlot

#------------------------------------------------------------------------------#
# Exercise
#------------------------------------------------------------------------------#
# 1. Create a simple line plot 
#    showing the funding over time 
#    with lines coloured by sport

# 2. Ensure the labels are added/updated 
# where appropriate


#------------------------------------------------------------------------------#
# Defining Scales
#------------------------------------------------------------------------------#

labels <- c(
  "Sydney\n(2000)", "Athens\n(2004)", 
  "Beijing\n(2008)", "London\n(2012)", 
  "Rio de Janeiro\n(2016)")

axisPlot <- labelPlot +
  scale_y_continuous(
    breaks = seq(0, 25e7, by = 5e7),
    minor_breaks = NULL, 
    labels = scales::dollar_format("£")) +
  scale_x_discrete(labels = labels)

axisPlot


cols <- c(
  "grey", "darkRed", "orangeRed", 
  "steelBlue", "royalBlue", "navyBlue")

fillPlot <- axisPlot +
  scale_fill_manual(values = cols)

fillPlot


#------------------------------------------------------------------------------#
# Exercise 
#------------------------------------------------------------------------------#

# 1. Update the x-axis to show Olympic 
#    years in Month-Year format 
#    (e.g. Sep 2000)

# 2. Update the y-axis to have the "£" 
#    symbol in front of the funding values



#------------------------------------------------------------------------------#
# Updating Legends
#------------------------------------------------------------------------------#


legendPlot <- fillPlot +
  theme(
    legend.position = "bottom", 
    legend.justification = "left")

legendPlot

guidePlot <- legendPlot +
  guides(
    fill = guide_legend(
      title.position = "top",
      nrow = 1, 
      label.position = "bottom"))

guidePlot


#------------------------------------------------------------------------------#
# Exercise
#------------------------------------------------------------------------------#

# 1. Move the legend underneath the 
#    graphic, select an appropriate 
#    alignment for the legend


# 2. Override the aes values in the 
#    guide so that the size of the line 
#    is 4 (hint: override.aes)


# 3. Adjust the title position and number 
#    of columns based on your legend alignment


#------------------------------------------------------------------------------#
# Controlling the Theme 
#------------------------------------------------------------------------------#

# search in ggplot2 for themes
objects("package:ggplot2", pattern = "theme_")

# collect current ggplot theme
theme_now <- theme_get()
# theme object containing theme information
class(theme_now)
length(theme_now)
head(names(theme_now))
theme_now["line"]

# all further plots have theme specified
theme_set(theme_classic())

guidePlot

# update theme
theme_update(axis.text.y = element_text(angle = 45),
             panel.grid.major.y = element_line(colour = "lightgrey"))

guidePlot

theme_set(theme_now)

guidePlot

# add themes to plots
guidePlot + theme_bw()

# later layers override previous layers
guidePlot + theme_bw() + 
    theme(legend.position = "bottom")

# theme object
theme_new <- theme_classic() +
    theme(
        legend.position = "bottom", 
        legend.justification = "left")
guidePlot + theme_new


#------------------------------------------------------------------------------#
# Exercise
#------------------------------------------------------------------------------#

# 1. Update the theme to include major grid lines 
#    that are dashed

# 2. Centre the title and subtitle