以编程方式生成 ggplot

Question

如何重新创建以下内容，以便不需要复制 geom_segment 行，而是以编程方式生成多个 geom_segment 调用（因此，可以使用许多不同的数据帧，这些数据帧的行数可能有所不同）？

library(ggplot2)
library(tibble)

df <- tibble::tibble(freqs = c(261.6256, 293.6648, 329.6276, 293.6648, 329.6276, 349.2282, 391.9954, 349.2282, 329.6276,
                       293.6648, 329.6276, 293.6648, 329.6276, 349.2282, 391.9954), 
             durs =  c(0.96, 1.92, 3.84, 4.80, 5.76,  7.68, 8.64, 9.60, 10.56, 11.52, 12.00, 12.48, 12.96, 13.44, 15.36))
df2 <- df

ggplot2::ggplot(df, ggplot2::aes(x = durs, y = freqs)) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[1],xend=df2$durs[2],y=df2$freqs[1],yend=df2$freqs[1])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[2],xend=df2$durs[3],y=df2$freqs[2],yend=df2$freqs[2])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[3],xend=df2$durs[4],y=df2$freqs[3],yend=df2$freqs[3])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[4],xend=df2$durs[5],y=df2$freqs[4],yend=df2$freqs[4])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[5],xend=df2$durs[6],y=df2$freqs[5],yend=df2$freqs[5])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[6],xend=df2$durs[7],y=df2$freqs[6],yend=df2$freqs[6])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[7],xend=df2$durs[8],y=df2$freqs[7],yend=df2$freqs[7])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[8],xend=df2$durs[9],y=df2$freqs[8],yend=df2$freqs[8])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[9],xend=df2$durs[10],y=df2$freqs[9],yend=df2$freqs[9])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[10],xend=df2$durs[11],y=df2$freqs[10],yend=df2$freqs[10])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[11],xend=df2$durs[12],y=df2$freqs[11],yend=df2$freqs[11])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[12],xend=df2$durs[13],y=df2$freqs[12],yend=df2$freqs[12])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[13],xend=df2$durs[14],y=df2$freqs[13],yend=df2$freqs[13])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[14],xend=df2$durs[15],y=df2$freqs[14],yend=df2$freqs[14])) +
  ggplot2::geom_segment(ggplot2::aes(x=df2$durs[15],xend=df2$durs[16],y=df2$freqs[15],yend=df2$freqs[15]))

Answer 1

ggplot(df, aes(x = durs, xend = dplyr::lead(durs), y = freqs, yend = freqs)) +
  geom_segment()

dplyr::lead或者，如果您想避免因某种原因需要使用，这里有一个基本 + ggplot2 解决方案。我创建了一个新向量，其中df2的durs值移动到前面出现的一行。

df2 <- df
df2$durs_next = c(df2$durs[seq_len(length(df2$durs)-1)+1], NA)
ggplot(df2, aes(x = durs, xend = durs_next, y = freqs, yend = freqs)) +
  geom_segment()