R 在ggplot中更改熔化df的颜色

我正试图改变以下ggplot的颜色，但发现很难做到这一点

mm <- melt(CashCycle, id= c('Ticker', 'Date'))
mm <- mm[mm$variable == "CollectionPeriod" | mm$variable == "DaysofInventory" | mm$variable == "DaysofPayable",]
mm$value <- with(mm, ifelse(variable == "DaysofPayable", -value, value))
ggplot(data = mm, aes(x = Date, y = value, fill = variable)) + 
  geom_bar(stat = 'identity', position = 'dodge') +
  labs(x="Year", y="Days") +
  theme_bw() +
  guides(color=guide_legend("Legend"))

---

使用

scale\u fill\u手册

ggplot(data = mm, aes(x = Date, y = value, fill = variable)) + 
  geom_bar(stat = 'identity', position = 'dodge') +
  scale_fill_manual(values = c("red", "blue", "orange")) +
  labs(x="Year", y="Days") +
  theme_bw() +
  guides(color=guide_legend("Legend"))

谢谢它工作得很好！：）下次将记住

scale\u fill\u manual（）

。

ggplot(data = mm, aes(x = Date, y = value, fill = variable)) + 
  geom_bar(stat = 'identity', position = 'dodge') +
  scale_fill_manual(values = c("red", "blue", "orange")) +
  labs(x="Year", y="Days") +
  theme_bw() +
  guides(color=guide_legend("Legend"))