How to reverse legend (labels and color) so high value starts downstairs?

Question

whats the best way to invert the legend label order so the 7 is down and the 1 is upstairs?

Answer 1

If you're putting it in numeric and it's a continuous scale, you're better off with scale_fill_continuous(trans = 'reverse') or scale_colour_continuous. Using your code, this would give:

ggplot(subset(df,feedback==1&stp>20), aes(x=correct, fill=day, colour=day)) +
    geom_histogram(colour="black", binwidth=10) +
    facet_grid(day ~ .) +
    ggtitle("Over-pronation histogram") +
    ylab("Count (150s period)") +
    xlab("% Steps in over-pronation")+
    scale_fill_continuous(trans = 'reverse')