Question

我想在R中创建一个绘图，但存在以下问题：我想将日期和时间作为标签添加到每个点。日期和时间在我的Excel工作表的两个单独的列中。到目前为止，我已经尝试过：geom_text（aes（label = time））。 R给我正确的时间，但给我的日期不正确。 R添加当前日期，而不是我的Excel工作表中写入的日期。

编辑：

我的数据如下：

dput(test) 
structure(list(date = c("01.08.2018", "01.08.2018", "02.08.2018", "02.08.2018", "03.08.2018", "03.08.2018"), 
               time = structure(c(1560943664, 1560943687, 1560943741, 1560946280, 1560946323, 1560946383), 
                                class = c("POSIXct", "POSIXt"), tzone = ""), 
               north = c(6172449.577, 6172438.383, 6172438.596, 6172491.3, 6172492.683, 6172504.024), 
               east = c(222251.4534, 222251.0842, 222250.4152, 222250.7746, 222256.5543, 222252.3612), 
               number = c(1L, 1L, 2L, 2L, 3L, 3L)), 
          row.names = c(NA, -6L), 
          class = "data.frame")

这是我的代码：

options(stringsAsFactors = FALSE) 
input2 <- "C:\\Users\\test.csv" 
test<- read.csv(input2, sep=";") 
test$time <- as.POSIXct(test$time, format = "%H:%M:%S") 

library(ggplot2) 

# dput(test) 

plot <- ggplot(test, aes(x=east, y=north, size="9", group=number)) + 
  geom_point() + geom_line(linetype="dashed", size=1) + 
  geom_text(aes(label=time),hjust=0, vjust=1.5) + 
  theme(legend.position="none")

print(plot)

Answer 1

使用substr和paste，您可以创建一个新变量，该变量具有date变量的日期和time变量的时间，然后将此新变量用于ggplot标签。

df <- structure(list(date = c("01.08.2018", "01.08.2018", "02.08.2018", "02.08.2018", "03.08.2018", "03.08.2018"), time = structure(c(1560943664, 1560943687, 1560943741, 1560946280, 1560946323, 1560946383), class = c("POSIXct", "POSIXt"), tzone = ""), north = c(6172449.577, 6172438.383, 6172438.596, 6172491.3, 6172492.683, 6172504.024), east = c(222251.4534, 222251.0842, 222250.4152, 222250.7746, 222256.5543, 222252.3612), number = c(1L, 1L, 2L, 2L, 3L, 3L)), row.names = c(NA, -6L), class = "data.frame")

df <- df %>% 
  mutate(date = as.Date(date, "%m.%d.%Y")) %>%
  mutate(t = substr(time, 12,19)) %>%
  mutate(dt = paste(date,t, sep = " "))

ggplot(df, aes(x=east, y=north, size="9", group=number)) + 
  geom_point() + 
  geom_line(linetype="dashed", size=1) + 
  geom_text(aes(label=dt),hjust=0, vjust=1.5) + 
  theme(legend.position="none")

如何在ggplot中的点上添加日期和时间？

1 个答案: