CODEWITHSUNDEEP
rggplot2facet
user3022875
user3022875

Reputation: 9018

how do you control color using facet_wrap() and ggplot

I have a graph that look like this:

x = c( rep(c(1,2,3,4,5),4)  )
group = c( rep(c(10,10,10,10,10),2),rep(c(20,20,20,20,20),2) )
value = rnorm(20)
dat = data.frame( x= x , group  = group, value = value)
dat = dat %>% # create the mu, sd, q1 and q3 aggregates
  group_by(group,x)  %>%  
  summarise(mu =  round(mean(value),2), 
            sd= sqrt(round(sd(value),2)), 
            Q1 = quantile(value)[2],
            Q3 = quantile(value)[4],
            count = n())
dat
dat2 = dat %>%  gather (key = Metric, value= Value,c(mu, sd, Q1, Q3)) #melt the data
as.data.frame(dat2)
ggplot(data=dat2 , aes(x=x, y=Value, group = Metric,colour = Metric)) + 
  geom_line()  + geom_point() + ylab("value") + 
  xlab("v") + 
  scale_x_discrete(breaks = c( seq(1,5,1)  ) ) +
  theme(axis.text.x = element_text(angle = 90, hjust = 1)) +
  scale_y_continuous(breaks = c( seq(-3,3,.25)  )  ) +
  scale_colour_manual(values=c("blue", "blue", "red","red")) + 
  facet_wrap(~ group, ncol=3)

enter image description here

For each group the lines are the sd, mean, 1st and 3rd quartiles. I would like the mean and sd to be BLUE and the 1st and 3rd quartiles to be RED. You can see that the colors are not correct.

(1) How can I control the colors of the lines so that sd and mean are blue and quartiles are red?

(2) How can I make the legend match the lines too? Thank you.

Upvotes: 1

Views: 3473

Answers (1)

steveb
steveb

Reputation: 5532

You can change the values vector in scale_colour_manual as follows:

scale_colour_manual(values=c(mu = "blue", sd = "blue", Q1 = "red", Q3 = "red"))

This way, order won't matter.

The full ggplot command would be:

ggplot(data=dat2 , aes(x=x, y=Value, group = Metric,colour = Metric)) + 
  geom_line()  + geom_point() + ylab("value") + 
  xlab("v") + 
  scale_x_discrete(breaks = c( seq(1,5,1)  ) ) +
  theme(axis.text.x = element_text(angle = 90, hjust = 1)) +
  scale_y_continuous(breaks = c( seq(-3,3,.25)  )  ) +
  scale_colour_manual(values=c(mu = "blue", sd = "blue", Q1 = "red", Q3 = "red")) + 
  facet_wrap(~ group, ncol=3)

Upvotes: 2

Related Questions