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Bar Chart in Colour and no Legend

20200428

ds %>%
  ggplot(aes(wind_dir_3pm, fill=wind_dir_3pm)) +
  geom_bar() +
  scale_y_continuous(labels=comma) +
  labs(x=vnames["wind_dir_3pm"], y="Count") +
  theme(legend.position="none")

Colour can add interest to a plot, though it is usually good to use the colour to communicate further information about the data. In this example we add a spread of colour across the bars by specifying the aesthetic fill=wind_dir_3pm. Thus the colour used is controlled by the values of the variable wind_dir_3pm. This is also the variable being plotted on the x-axis and so as an example it adds no new information to the plot. A good set of colours is chosen by default and could be changed through themes.

We add a ggplot2::theme() element here to remove the legend that would be displayed by default, by indicating that the legend.position="none". An alternative to turn the legend off is to provide show.legend=FALSE to the layer (i.e., ggplot2::geom_bar()). This then allows layer specific control of the legends.