Every time I make a plot using ggplot, I spend a little while trying different values for hjust and vjust in a line like
+ opts(axis.text.x = theme_text(hjust = 0.5))
to get the axis labels to line up where the axis labels almost touch the axis, and are flush against it (justified to the axis, so to speak). However, I don’t really understand what’s going on. Often, hjust = 0.5 gives such dramatically different results from hjust = 0.6, for example, that I haven’t been able to figure it out just by playing around with different values.
Can anyone point me to a comprehensive explanation of how hjust and vjust options work?