geom_line 在 R 中按年份分组

Question

我正在尝试通过对 year 列进行分组来创建一些数据的时间序列图。在下面的代码中，当我尝试通过 year 来 gather 值时，该函数会选择另一列的 header (tmean) 作为 key，这是我想要的year 列下的值为 key.

我该如何解决这个问题？

示例数据

Date = c("2010-01", "2010-02", "2010-03","2010-04", "2011-01", "2011-02", "2011-03", "2011-04")
year = c(2010, 2010, 2010, 2010, 2011, 2011, 2011, 2011)
month = c(01, 02, 03, 04, 01, 02, 03, 04)
tmean = c(15, 20, 30, 25, 18, 23, 33, 28)

代码

library(tidyverse)

df = data.frame(tmean. Date, year, month)

df = df %>% 
  select(Date, tmean, year) %>% 
  gather(key = "variable", value = "value", -Date)

ggplot(df, aes(x = Date, y = value)) + 
  geom_line(aes(color = variable, linetype = variable)

想要的情节

Answer 1

如果你想生成你想要的图，你真的不需要重塑你的数据框。

library(ggplot2)

Date = c("2010-01", "2010-02", "2010-03","2010-04", "2011-01", "2011-02", "2011-03", "2011-04")
year = c(2010, 2010, 2010, 2010, 2011, 2011, 2011, 2011)
month = c(01, 02, 03, 04, 01, 02, 03, 04)
tmean = c(15, 20, 30, 25, 18, 23, 33, 28)
df = data.frame(tmean, Date, year, month)

ggplot(df, aes(month, tmean, color = as.character(year))) + 
  geom_line() +
  labs(color = "Year")

^{由 reprex package (v2.0.1)}

创建于 2022-04-02

geom_line 在 R 中按年份分组

geom_line group by year in R

r

ggplot2

tidyverse