使用 geom_line 绘制多条线（基于分组）

请帮助我，关于当我尝试在 ggplot2 中使用 geom_line 绘制分组的多条线时遇到的问题。 当我尝试根据一个变量/列（即：区域）对行进行分组时，问题就出现了。

GDP_time_series_analysis %>% 
  group_by(Region) %>% 
  ggplot()+geom_line(aes(Year, Total_GDP, group=Region, color=Region))

The code that I provide produces the following graph: it is correct graph only for one region (purple line) that consists of only one county (another variable), but not for the other 3 regions that have more counties. I suppose there is a problem with grouping, I am not able to group other 3 regions as a group for the graph (although, as you see, I did use group_by (Region) in the code).

很抱歉，如果这个问题不是完全不符合标准（这是我第一次在这里），谢谢。 数据子集如下：

 structure(list(County = c("City of Zagreb", "City of Zagreb", 
"City of Zagreb", "City of Zagreb", "City of Zagreb", "City of Zagreb", 
"City of Zagreb", "City of Zagreb", "City of Zagreb", "City of Zagreb", 
 "City of Zagreb", "City of Zagreb", "City of Zagreb", "City of Zagreb", 
 "City of Zagreb", "City of Zagreb", "City of Zagreb", "City of Zagreb", 
 "Zagreb County", "Zagreb County", "Zagreb County", "Zagreb County", 
 "Zagreb County", "Zagreb County", "Zagreb County", "Zagreb County", 
 "Zagreb County", "Zagreb County", "Zagreb County", "Zagreb County"
  ), Region = c("Zagreb", "Zagreb", "Zagreb", "Zagreb", "Zagreb", 
 "Zagreb", "Zagreb", "Zagreb", "Zagreb", "Zagreb", "Zagreb", "Zagreb", 
  "Zagreb", "Zagreb", "Zagreb", "Zagreb", "Zagreb", "Zagreb", "North        Croatia", 
 "North Croatia", "North Croatia", "North Croatia", "North Croatia", 
 "North Croatia", "North Croatia", "North Croatia", "North Croatia", 
  "North Croatia", "North Croatia", "North Croatia"), Year = c(2000, 
  2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 
  2012, 2013, 2014, 2015, 2016, 2017, 2000, 2001, 2002, 2003, 2004, 
  2005, 2006, 2007, 2008, 2009, 2010, 2011), Population = c(771000, 
  771000, 772000, 772000, 775000, 776000, 778000, 780000, 783000, 
   785000, 788000, 790000, 792000, 795000, 798000, 8e+05, 802000, 
  803000, 296000, 296000, 299000, 302000, 305000, 307000, 310000, 
  312000, 314000, 315000, 317000, 317000), GDP_percap_EUR =        c(8975.53835599625, 
  10168.0040269207, 11091.6676199461, 12240.0345558531, 13421.0447587177, 
   15085.3049042075, 16647.4994908354, 18025.966664434, 19706.5391945802, 
   18534.1115208295, 19739.3466772558, 19408.6216726494,          18961.2735614516, 
   18546.0140474649, 18477.4378485715, 18994.6373722612, 19710.3754557913, 
  20849.7073006642, 4335.38213876616, 4307.23697694032, 5278.97949713334, 
  5459.93196849043, 5967.08989896781, 6687.19494658443, 6861.43232701965, 
  7759.05700432905, 8446.22608743048, 8086.60105100451, 7541.08792074132, 
  7667.23597749996), GDP_percap_PPP_EU_100 = c(80.0982702062271, 
  82.6988344044675, 85.4138484640405, 91.204873884138, 93.9216165828703, 
  99.0724656137407, 104.305150969215, 107.963791825045, 111.305636873515, 
  109.91689646398, 111.438020798517, 110.735014385039, 110.140140004045, 
  107.718076160351, 105.910224718338, 106.327225119802, 107.021331220602, 
  108.151130040081, 38.6892235568413, 35.0317994125204, 40.6519533638096, 
  40.6839052888146, 41.7582043486098, 43.9180311969089, 42.9904043624586, 
  46.4716944599064, 47.7056151035234, 47.9577394076775, 42.5730357896448, 
  43.7450685876577), Total_GDP = c(6920140072.47311, 7839531104.75587, 
  8562767402.59836, 9449306677.11856, 10401309688.0062, 11706196605.665, 
  12951754603.8699, 14060253998.2585, 15430220189.3563, 14549277543.8512, 
  15554605181.6776, 15332811121.393, 15017328660.6697, 14744081167.7346, 
   14744995403.16, 15195709897.809, 15807721115.5446, 16742314962.4333, 
  1283273113.07478, 1274942145.17433, 1578414869.64287, 1648899454.48411, 
  1819962419.18518, 2052968848.60142, 2127044021.37609, 2420825785.35066, 
  2652114991.45317, 2547279331.06642, 2390524870.875, 2430513804.86749
   )), row.names = c(NA, -30L), class = c("tbl_df", "tbl", "data.frame"
    ))

问题是，您的数据位于县级别，但您将其绘制在区域上（粒度较小）。如果您尝试按照您的方式直接绘制数据，您最终会得到每组多个值。您必须应用汇总统计数据才能获得一些有意义的结果。

这是使用一些虚拟数据的小插图：

df <- tibble(County = rep(c("Krapina-Zagorje", "Varaždin","Zagreb"), each = 3),
         Region = rep(c("North Croatia","North Croatia","Zagreb"), each = 3),
         Year = rep(2015:2017,3),
         GDP = 1:9)
ggplot(df, aes(x = Year, y = GDP, colour =Region, group = Region)) +  geom_line() + geom_point()

由于每组只需要一个值，因此您必须相应地汇总数据（我假设您对每组的总和感兴趣）：

ggplot(df, aes(x = Year, y = GDP, colour =Region, group = Region)) + stat_summary(fun = sum, geom = "line")