在使用reshape2
将数据融合后,如何使用geom_segment
在图表上绘制线条?
# Tiny dataset
facet_group <- c("facet1", "facet1", "facet2", "facet2")
time_group <- c("before", "after", "before", "after")
variable1 <- c(1,5,4,7)
variable2 <- c(2,4,5,8)
variable3 <- c(4,5,6,7)
data <- data.frame(facet_group, time_group, variable1, variable2, variable3)
# Melt data
library(reshape2)
data_melt <- melt(data, id.vars = c("facet_group", "time_group"))
绘制数据:
# Plot 1
library(ggplot2)
ggplot(data_melt, aes(x=variable, y=value, group = time_group)) +
geom_point(aes(color = time_group))
添加分面:
# Plot 2
ggplot(data_melt, aes(x=variable, y=value, group = time_group)) +
geom_point(aes(color = time_group)) +
facet_grid(facet_group ~ .)
我想为每个变量从“前”点绘制线段到“后”点(见模拟图)。如何做到这一点?我使用了geom_segment
,但是出现了错误。将数据转换为新的数据框是否有帮助?谢谢!
data_cast <- dcast(data_melt, variable + facet_group ~ time_group)
最终“理想”的图表:
geom_segment
函数非常关键,但将time_group
变量从ggplot()
函数移动到geom_point
函数也同样重要。谢谢! - Todd