ggplot2：创建包含多个符号，线型和颜色的图例

Question

我正在尝试创建一个函数来绘制测量的流值（作为未连接的点），以及建模值的平滑曲线。我希望能够为每种类型的流量（15分钟与24小时）制作独特的形状，并且还具有两种模型流程的独特颜色和线型。

我已经能够为我的测量值创建不同的颜色并在图例中正确显示，但是当我尝试改变形状时，我遇到了麻烦。尝试匹配曲线中的虚线和实线也是一样的。我尝试将geom_point（）+更改为geom_point（shape = variable）+但是会产生此错误：图层中的错误（data = data，mapping = mapping，stat = stat，geom = GeomLine，：object'variable'not found

ggplot(data = r1,aes(x=ReturnPeriod, y=value, color=variable)) +
  geom_point()+
  geom_line(data = r2,aes(x=ReturnPeriod, y=value))+
  ylab("Max Yearly Flow (cfs)") +
  xlab("Return Interval (years)") +
  scale_shape_manual(name = "Legend", 
                      labels = c("Obs 15-min", "Obs 24-hour", "15-min P3", "24-hr P3"),
                      values = c("Peak_cfs"=16, "Daily_cfs"=17, "PeakEst"=NA, 
                                 "DailyEst" = NA)) +
  scale_colour_manual(name = "Legend", 
                      labels = c("Obs 15-min", "Obs 24-hour", "15-min P3", "24-hr P3"),
                      values = c("Peak_cfs"="grey", "Daily_cfs"="black", "PeakEst"="dark grey", 
                                 "DailyEst" = "black")) +
  scale_linetype_manual(name = "Legend", 
                        labels = c("Obs 15-min", "Obs 24-hour", "15-min P3", "24-hr P3"),
                        values = c("Peak_cfs"="blank", "Daily_cfs"="blank", "PeakEst"="solid", 
                                   "DailyEst" = "dashed"))+
  guides(colour = guide_legend(override.aes = list(
    linetype = c("blank", "blank", "solid", "dashed"),
    shape = c(16,17,NA,NA),
    color = c("grey","black", "dark grey", "black")))) +
  theme(legend.position=c(0.92, 0.2),  
        legend.background = element_rect(fill="white"),
        legend.key = element_blank(),
        legend.box = "horizontal")

我的数据是：

r1 = read.table(
  header = TRUE,
  stringsAsFactors = FALSE,
  text = 
"ReturnPeriod  variable value
1      1.090909 Daily_cfs  14.3
2      1.200000 Daily_cfs  52.3
3      1.333333 Daily_cfs  66.6
4      1.500000 Daily_cfs  93.3
5      1.714286 Daily_cfs  94.3
6      2.000000 Daily_cfs 103.0
7      2.400000 Daily_cfs 107.0
8      3.000000 Daily_cfs 119.0
9      4.000000 Daily_cfs 123.0
10     6.000000 Daily_cfs 166.0
11    12.000000 Daily_cfs 207.0
12     1.090909  Peak_cfs  29.0
13     1.200000  Peak_cfs 159.0
14     1.333333  Peak_cfs 241.0
15     1.500000  Peak_cfs 255.0
16     1.714286  Peak_cfs 296.0
17     2.000000  Peak_cfs 320.0
18     2.400000  Peak_cfs 339.0
19     3.000000  Peak_cfs 351.0
20     4.000000  Peak_cfs 512.0
21     6.000000  Peak_cfs 737.0
22    12.000000  Peak_cfs 800.0"
)

r2 <- read.table(
  header = TRUE,
  stringsAsFactors = FALSE,
  text = 
    "ReturnPeriod variable      value
1      1.010101 DailyEst   8.185016
2      2.000000 DailyEst 104.434396
3      4.000000 DailyEst 148.084828
4     10.000000 DailyEst 180.992656
5     25.000000 DailyEst 199.429333
6     50.000000 DailyEst 207.967918
7      1.010101  PeakEst  14.846387
8      2.000000  PeakEst 349.352462
9      4.000000  PeakEst 547.379809
10    10.000000  PeakEst 713.827969
11    25.000000  PeakEst 815.243158
12    50.000000  PeakEst 865.063562"
)

我期待在图表中获得24小时Obs的三角形符号，而不是我得到圆圈，在图例和图形中，我试图将纯黑线变为黑色虚线。

当前代码生成的图表：

Answer 1

如果你将r1和r2组合到r3进行绘图并将shape + linetype添加到aes，它将起作用

library(ggplot2)

r1$variable <- factor(r1$variable)
r2$variable <- factor(r2$variable)
r3 <- rbind(r1, r2)

ggplot(data = r3, aes(x=ReturnPeriod, y=value, color=variable, shape=variable)) +
  geom_point()+
  geom_line(aes(linetype=variable))+
  ylab("Max Yearly Flow (cfs)") +
  xlab("Return Interval (years)") +
  scale_shape_manual(name = "Legend", 
                     labels = c("Obs 15-min", "Obs 24-hour", "15-min P3", "24-hr P3"),
                     values = c("Peak_cfs"=16, "Daily_cfs"=17, "PeakEst"=NA, 
                                "DailyEst" = NA)) +
  scale_colour_manual(name = "Legend", 
                      labels = c("Obs 15-min", "Obs 24-hour", "15-min P3", "24-hr P3"),
                      values = c("Peak_cfs"="grey", "Daily_cfs"="black", "PeakEst"="dark grey", 
                                 "DailyEst" = "black")) +
  scale_linetype_manual(name = "Legend",
                        labels = c("Obs 15-min", "Obs 24-hour", "15-min P3", "24-hr P3"),
                        values = c("Peak_cfs"="blank", "Daily_cfs"="blank", "PeakEst"="solid",
                                   "DailyEst" = "dashed"))+
  guides(colour = guide_legend(override.aes = list(
    linetype = c("blank", "blank", "solid", "dashed"),
    shape = c(16,17,NA,NA),
    color = c("grey","black", "dark grey", "black")))) +
  theme(legend.position=c(0.8, 0.6),  
    legend.background = element_rect(fill="white"),
    legend.key = element_blank(),
    legend.box = "horizontal")
#> Warning: Removed 12 rows containing missing values (geom_point).

Answer 2

你需要告诉ggplot如何通过包含geom_point(aes(shape = factor(variable)))来分组形状

然后你需要在scale_shape_manual(values = c(19, 17))中调用一个值，告诉ggplot使用哪些符号（在这种情况下是实心圆和实心三角形）。这应该是你对values的当前列表而不是。

同样，对于geom_line调用和两种线类型，您需要包含组因子和线型值。

看看有关ggplot2 pages的一些好建议