无法使用ggplot更改图例标题和标签

Question

我想更改ggplot中的标题和标签。 我现在有以下代码：

ggplot() +
geom_line(data = VW_activations, aes(x = VW_activations$Month, y = 
VW_activations$Activations, color = VW_activations$Country), size = 1.2)+
theme_light(base_size = 11, base_family = "")+
xlab("Date")+
ylab("Number of contract activations")+
scale_fill_discrete(name="Country", labels=c("AT", "BE", "CH", "DE", "ES", 
"FI", "FR", "IT", "LU", "NL", "NO", "PT", "UK"))

但是，这不起作用，图例标题只是VW_activations $ Country。 有人知道我在做什么错吗？

Answer 1

那这个呢：

ggplot() +
  geom_line(data = VW_activations, aes(x = Month, y = Activations, color = Country), size = 1.2)+
  theme_light(base_size = 11, base_family = "")+
  xlab("Date")+
  ylab("Number of contract activations")+
  scale_color_manual(name="Country", labels=c("AT", "BE"), values =c("red","green"))

要没有手动设置颜色数量，可以使用软件包RColorBrewer ：

library(RColorBrewer)
ggplot() +
  geom_line(data = VW_activations, aes(x = Month, y = Activations, color = Country), size = 1.2)+
  theme_light(base_size = 11, base_family = "")+
  xlab("Date")+
  ylab("Number of contract activations")+
  scale_color_manual(name="Country", labels=c("AT", "BE"),
  # here we define a scale of color between red and blue f.e., and generate
  # n colors n == numbers of country in this case
  values =colorRampPalette(c("red", "blue"))(length(unique(VW_activations$Country)))
   )

或者：

... values = brewer.pal(n = length(unique(VW_activations$Country)), name = "Set2")...

没有渐变“褪色”的颜色。 附带数据：

VW_activations <-data.frame(Country = c("K","J","K","J"),
                            Month = c(1,1,2,2),
                            Activations = c(11,13,55,66))

Answer 2

这样行吗？ （如果附加一些数据，则更容易回答您的问题）。

ggplot() +
    geom_line(data = VW_activations, aes(x = VW_activations$Month, 
                                         y = VW_activations$Activations, 
                                         color = VW_activations$Country), 
              size = 1.2) +
    theme_light(base_size = 11, base_family = "") +
    labs(
        x = "Date",
        y = "Number of contract activations",
        fill = "Country"
        ) +
    scale_fill_discrete(labels = c("AT", "BE", "CH", "DE", "ES", "FI", "FR", 
                                   "IT", "LU", "NL", "NO", "PT", "UK"))