Possible intro to using palettes, viridis_theme to adjust for colorblindness.

[Averysaurus]

The reprex below builds on the plots already put together in the main .RMD while adding a few color palette libraries, functions and arguments.

    library(colorspace)

    # the palettes colorspace has bundled. 
    colorspace::hcl_palettes(plot = TRUE)

   # "_Error in plot.new() : figure margins too large_" return?
    # pull your plot window to the left, and/or click "Zoom" button to view all the palettes together. 

    dyn_pal <- qualitative_hcl(5, palette = "Dynamic")
    # function is explict about what kind of scale:
    # see qualitative_hcl(), sequential_hcl(), diverging_hcl().
    # first argument specifies the n of colors, second is the palette name from chart. 
    dyn_pal

    # assigning colors explicitly. 
    boxplot(gap$lifeExp ~ gap$continent, 
        # Give each box its own color
     col = c("orange", "blue", "green", "red", "purple"))

    # using a palette assign colors with base R. 
    boxplot(gap$lifeExp ~ gap$continent, 
        # Draw colors from a special palette 
        col = dyn_pal)

    # ggplot without palette function added. 
    ggplot(data = gap, aes(x = gdpPercap, y = lifeExp, color = continent)) + 
    geom_point() + 
    theme(legend.position = "right")

    # using a palette.
    ggplot(data = gap, aes(x = gdpPercap, y = lifeExp, color = continent)) + 
    geom_point() + 
    # we can add a palette layer to our ggplot chunk from the names availble in hcl_palettes(). 
       colorspace::scale_color_discrete_sequential(palette = "Red-Blue")
    # unless an nmax() argument is specified, color assignments are automatically calculated from the distribution of the data. 

    install.packages("viridis")
    library(viridis)

     # It's estimated that, "_globally, 1 in 12 males and 1 in 200 females are colorblind._" The most common form of color 
    blindness is red-green color blindness. **Viridis** is a color palette with an emphasis on accessibility for those of us who 
    experience colorblindness.

    [Viridis](https://cran.r-project.org/web/packages/viridis/vignettes/intro-to-viridis.html)

    [Learn More about colorblindness](https://en.wikipedia.org/wiki/Color_blindness)

    # plots with viridis theme added.
    ggplot(data = gap, aes(x = continent, y = lifeExp, fill = continent)) + 
      geom_boxplot() + 
      viridis::scale_fill_viridis(discrete=TRUE)

   ggplot(data = gap, aes(x = gdpPercap, y = lifeExp, color = continent)) + 
      geom_point() + 
      theme(legend.position = "right") +
    viridis::scale_color_viridis(discrete=TRUE) 

    # Base R plotting with viridis. 
    # create a palette
    vir_pal <- sequential_hcl(5, palette = "Viridis")

    #plot with base. 
    boxplot(gap$lifeExp ~ gap$continent, 
        # Draw colors from a special palette 
        col = vir_pal)

# Note: Palettes and color theory are a whole other domain of art and design that R is super articulate about. With color palettes,  a focus on accessibility and avoidance of the "headache factor" are good principles to live by. 

[EastBayEv]

Thanks Avery, this is a great point. We will be sure to incorporate this into the other workshops at our first review at the end of the month!

[pssachdeva]

Closed by #12.