在极线 ggplot 图中加入间隙
Join gap in polar line ggplot plot
当 ggplot 使用极坐标绘制线图时,它会在最高和最低 x 值(下面的 Dec
和 Jan
之间留下间隙,而不是环绕成螺旋形。我怎样才能继续这条线并缩小差距?
特别是,我想使用月份作为我的 x 轴,但在一条循环线中绘制多年的数据。
代表:
library(ggplot2)
# three years of monthly data
df <- expand.grid(month = month.abb, year = 2014:2016)
df$value <- seq_along(df$year)
head(df)
## month year value
## 1 Jan 2014 1
## 2 Feb 2014 2
## 3 Mar 2014 3
## 4 Apr 2014 4
## 5 May 2014 5
## 6 Jun 2014 6
ggplot(df, aes(month, value, group = year)) +
geom_line() +
coord_polar()
这里有一个 somewhat-hacky 选项:
# make a data.frame of start values end values should continue to
bridges <- df[df$month == 'Jan',]
bridges$year <- bridges$year - 1 # adjust index to align with previous group
bridges$month <- NA # set x value to any new value
# combine extra points with original
ggplot(rbind(df, bridges), aes(month, value, group = year)) +
geom_line() +
# close gap by removing expansion; redefine breaks to get rid of "NA/Jan" label
scale_x_discrete(expand = c(0,0), breaks = month.abb) +
coord_polar()
显然,添加额外的数据点并不理想,因此可能存在更优雅的答案。
当 ggplot 使用极坐标绘制线图时,它会在最高和最低 x 值(下面的 Dec
和 Jan
之间留下间隙,而不是环绕成螺旋形。我怎样才能继续这条线并缩小差距?
特别是,我想使用月份作为我的 x 轴,但在一条循环线中绘制多年的数据。
代表:
library(ggplot2)
# three years of monthly data
df <- expand.grid(month = month.abb, year = 2014:2016)
df$value <- seq_along(df$year)
head(df)
## month year value
## 1 Jan 2014 1
## 2 Feb 2014 2
## 3 Mar 2014 3
## 4 Apr 2014 4
## 5 May 2014 5
## 6 Jun 2014 6
ggplot(df, aes(month, value, group = year)) +
geom_line() +
coord_polar()
这里有一个 somewhat-hacky 选项:
# make a data.frame of start values end values should continue to
bridges <- df[df$month == 'Jan',]
bridges$year <- bridges$year - 1 # adjust index to align with previous group
bridges$month <- NA # set x value to any new value
# combine extra points with original
ggplot(rbind(df, bridges), aes(month, value, group = year)) +
geom_line() +
# close gap by removing expansion; redefine breaks to get rid of "NA/Jan" label
scale_x_discrete(expand = c(0,0), breaks = month.abb) +
coord_polar()
显然,添加额外的数据点并不理想,因此可能存在更优雅的答案。