在极坐标图上绘制曲线
Plotting Curved Lines on Polar Charts
我正在尝试创建一个图表，用于绘制点、标签和连接给定起点和终点位置的点的线。然后将其转化为极坐标图。我可以绘制点、标签和线条，但我的问题是当我将图表转换为极坐标时。 geom_curve 和 geom_segment.
我都用过
在使用 geom_curve 时出现错误，因为 geom_curve 未针对非线性坐标实现。因此，我能得到的最远的是：
在使用 geom_segment 时，它更接近我想要的效果，但它沿着圆周绘制线条，考虑到我如何通过坐标，这是有道理的。这是一张照片：
我基本上需要一个 geom_curve 的极坐标，但一直找不到。我想要圆圈内侧的线条和曲线，会有一些重叠，但无论如何建议它看起来很漂亮，间距或其他东西会受到欢迎。
数据：
k<-18
ct<-12
q<-6
x_vector1<-seq(1,k,1)
x_vector2<-seq(1,3,1)
x_vector3<-seq(k-2,k,1)
x_vector<-c(x_vector1,x_vector2,x_vector3)
n<-9 ## sets first level radius
radius1<-rep(n,k)
b<-13 ## sets second level radius
radius2<-rep(b,q)
radius<-c(radius1,radius2)
name<-c('Alice','Bob','Charlie','D','E','F','G','H','I','J','K','L',
'M','N','O','Peter','Quin','Roger','Alice2','Bob2','Charlie2',
'Peter2','Quin2','Roger2')
dframe<-data.frame(x_vector,radius,name)
dframe$label_radius<-dframe$radius+1
from<-c('Alice2','Bob','Charlie','D','E','Alice2','Charlie2','Charlie',
'I','J','K','L','M','N','O','Peter','Quin','Alice')
to<-c('Alice','Alice','Alice','Alice','Alice','Bob',
'Bob','Bob','Bob','Charlie','Charlie','Peter',
'Peter','Quin','Quin','Quin','Roger','Roger')
amt<-c(3,8,8,8,6,2,2,4,2,4,8,1,10,5,9,5,2,1)
linethick<-c(0.34,0.91,0.91,0.91,0.68,0.23,0.23,0.45,0.23,0.45,
0.91,0.11,1.14,0.57,1.02,0.57,0.23,0.11)
to_x<-c(1,1,1,1,1,2,2,2,2,3,3,16,16,17,17,17,18,18)
to_rad<-c(9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9)
from_x<-c(1,2,3,4,5,1,3,3,9,10,11,12,13,14,15,16,17,1)
from_rad<-c(13,9,9,9,9,13,13,9,9,9,9,9,9,9,9,9,9,9)
stats<-data.frame(from,to,amt,linethick,to_x,to_rad,from_x,from_rad)
p<-ggplot()+
geom_point(data=dframe,aes(x=x_vector,y=radius),size=3,shape=19)+
geom_text(data=dframe,aes(x=x_vector,y=label_radius,label=name))+
geom_segment(data=stats,aes(x=from_x,y=from_rad,xend=to_x,yend=to_rad, color=to), ## I need arrows starting at TO and going to FROM. ##
arrow=arrow(angle=15,ends='first',length=unit(0.03,'npc'), type='closed'))+
## transform into polar coordinates coord_polar(theta='x',start=0,direction=-1)
## sets up the scale to display from 0 to 7 scale_y_continuous(limits=c(0,14))+
## Used to 'push' the points so all 'k' show up. expand_limits(x=0) p
你必须在 ggplot2 中做所有事情吗？
如果没有，那么一种选择是用点创建绘图（可能使用 ggplot2，或者只是直线网格图形，甚至可能是基础图形），然后推送到适当的视口并使用 xsplines 在之间添加曲线这些点（请参阅此答案：Is there a way to make nice "flow maps" or "line area" graphs in R? 了解使用 xspline 的基本示例）。
如果您坚持使用 ggplot2 做所有事情，那么您可能需要创建自己的 geom 函数来在极坐标图中绘制曲线。
正如其他人评论的那样，您可以通过自己在笛卡尔坐标系中计算来模拟 coord_polar() 产生的所需位置。即：
x = radius * cos(theta)
y = radius * sin(theta)
# where theta is the angle in radians
处理2个数据框：
dframe2 <- dframe %>%
mutate(x_vector = as.integer(factor(x_vector))) %>%
mutate(theta = x_vector / n_distinct(x_vector) * 2 * pi + pi / 2) %>%
mutate(x = radius * cos(theta),
y = radius * sin(theta),
y.label = label_radius * sin(theta),
name = as.character(name))
stats2 <- stats %>%
select(from, to, amt, linethick) %>%
mutate_at(vars(from, to), as.character) %>%
left_join(dframe2 %>% select(name, x, y),
by = c("from" = "name")) %>%
rename(x.start = x, y.start = y) %>%
left_join(dframe2 %>% select(name, x, y),
by = c("to" = "name")) %>%
rename(x.end = x, y.end = y)
绘图使用 geom_curve():
# standardize plot range in all directions
plot.range <- max(abs(c(dframe2$x, dframe2$y, dframe2$y.label))) * 1.1
p <- dframe2 %>%
ggplot(aes(x = x, y = y)) +
geom_point() +
geom_text(aes(y = y.label, label = name)) +
# use 2 geom_curve() layers with different curvatures, such that all segments align
# inwards inside the circle
geom_curve(data = stats2 %>% filter(x.start > 0),
aes(x = x.start, y = y.start,
xend = x.end, yend = y.end,
color = to),
curvature = -0.3,
arrow = arrow(angle=15, ends='first',
length=unit(0.03,'npc'),
type='closed')) +
geom_curve(data = stats2 %>% filter(x.start <= 0),
aes(x = x.start, y = y.start,
xend = x.end, yend = y.end,
color = to),
curvature = 0.3,
arrow = arrow(angle=15, ends='first',
length=unit(0.03,'npc'),
type='closed')) +
expand_limits(x = c(-plot.range, plot.range),
y = c(-plot.range, plot.range)) +
coord_equal() +
theme_void()
p
如果你想要极地网格线，也可以使用 geom_spoke() 和 ggfortify 包的 geom_circle():
来模拟这些
library(ggforce)
p +
geom_spoke(data = data.frame(x = 0,
y = 0,
angle = pi * seq(from = 0,
to = 2,
length.out = 9), # number of spokes + 1
radius = plot.range),
aes(x = x, y = y, angle = angle, radius = radius),
inherit.aes = FALSE,
color = "grey") +
geom_circle(data = data.frame(x0 = 0,
y0 = 0,
r = seq(from = 0,
to = plot.range,
length.out = 4)), # number of concentric circles + 1
aes(x0 = x0, y0 = y0, r = r),
inherit.aes = FALSE,
color = "grey", fill = NA)
（注意：如果您真的想要这些伪网格线，请在 之前 绘制其他几何图层。）
我正在尝试创建一个图表，用于绘制点、标签和连接给定起点和终点位置的点的线。然后将其转化为极坐标图。我可以绘制点、标签和线条，但我的问题是当我将图表转换为极坐标时。 geom_curve 和 geom_segment.
在使用 geom_curve 时出现错误，因为 geom_curve 未针对非线性坐标实现。因此，我能得到的最远的是：
在使用 geom_segment 时，它更接近我想要的效果，但它沿着圆周绘制线条，考虑到我如何通过坐标，这是有道理的。这是一张照片：
我基本上需要一个 geom_curve 的极坐标，但一直找不到。我想要圆圈内侧的线条和曲线，会有一些重叠，但无论如何建议它看起来很漂亮，间距或其他东西会受到欢迎。
数据：
k<-18
ct<-12
q<-6
x_vector1<-seq(1,k,1)
x_vector2<-seq(1,3,1)
x_vector3<-seq(k-2,k,1)
x_vector<-c(x_vector1,x_vector2,x_vector3)
n<-9 ## sets first level radius
radius1<-rep(n,k)
b<-13 ## sets second level radius
radius2<-rep(b,q)
radius<-c(radius1,radius2)
name<-c('Alice','Bob','Charlie','D','E','F','G','H','I','J','K','L',
'M','N','O','Peter','Quin','Roger','Alice2','Bob2','Charlie2',
'Peter2','Quin2','Roger2')
dframe<-data.frame(x_vector,radius,name)
dframe$label_radius<-dframe$radius+1
from<-c('Alice2','Bob','Charlie','D','E','Alice2','Charlie2','Charlie',
'I','J','K','L','M','N','O','Peter','Quin','Alice')
to<-c('Alice','Alice','Alice','Alice','Alice','Bob',
'Bob','Bob','Bob','Charlie','Charlie','Peter',
'Peter','Quin','Quin','Quin','Roger','Roger')
amt<-c(3,8,8,8,6,2,2,4,2,4,8,1,10,5,9,5,2,1)
linethick<-c(0.34,0.91,0.91,0.91,0.68,0.23,0.23,0.45,0.23,0.45,
0.91,0.11,1.14,0.57,1.02,0.57,0.23,0.11)
to_x<-c(1,1,1,1,1,2,2,2,2,3,3,16,16,17,17,17,18,18)
to_rad<-c(9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9,9)
from_x<-c(1,2,3,4,5,1,3,3,9,10,11,12,13,14,15,16,17,1)
from_rad<-c(13,9,9,9,9,13,13,9,9,9,9,9,9,9,9,9,9,9)
stats<-data.frame(from,to,amt,linethick,to_x,to_rad,from_x,from_rad)
p<-ggplot()+
geom_point(data=dframe,aes(x=x_vector,y=radius),size=3,shape=19)+
geom_text(data=dframe,aes(x=x_vector,y=label_radius,label=name))+
geom_segment(data=stats,aes(x=from_x,y=from_rad,xend=to_x,yend=to_rad, color=to), ## I need arrows starting at TO and going to FROM. ##
arrow=arrow(angle=15,ends='first',length=unit(0.03,'npc'), type='closed'))+
## transform into polar coordinates coord_polar(theta='x',start=0,direction=-1)
## sets up the scale to display from 0 to 7 scale_y_continuous(limits=c(0,14))+
## Used to 'push' the points so all 'k' show up. expand_limits(x=0) p
你必须在 ggplot2 中做所有事情吗？
如果没有，那么一种选择是用点创建绘图（可能使用 ggplot2，或者只是直线网格图形，甚至可能是基础图形），然后推送到适当的视口并使用 xsplines 在之间添加曲线这些点（请参阅此答案：Is there a way to make nice "flow maps" or "line area" graphs in R? 了解使用 xspline 的基本示例）。
如果您坚持使用 ggplot2 做所有事情，那么您可能需要创建自己的 geom 函数来在极坐标图中绘制曲线。
正如其他人评论的那样，您可以通过自己在笛卡尔坐标系中计算来模拟 coord_polar() 产生的所需位置。即：
x = radius * cos(theta)
y = radius * sin(theta)
# where theta is the angle in radians
处理2个数据框：
dframe2 <- dframe %>%
mutate(x_vector = as.integer(factor(x_vector))) %>%
mutate(theta = x_vector / n_distinct(x_vector) * 2 * pi + pi / 2) %>%
mutate(x = radius * cos(theta),
y = radius * sin(theta),
y.label = label_radius * sin(theta),
name = as.character(name))
stats2 <- stats %>%
select(from, to, amt, linethick) %>%
mutate_at(vars(from, to), as.character) %>%
left_join(dframe2 %>% select(name, x, y),
by = c("from" = "name")) %>%
rename(x.start = x, y.start = y) %>%
left_join(dframe2 %>% select(name, x, y),
by = c("to" = "name")) %>%
rename(x.end = x, y.end = y)
绘图使用 geom_curve():
# standardize plot range in all directions
plot.range <- max(abs(c(dframe2$x, dframe2$y, dframe2$y.label))) * 1.1
p <- dframe2 %>%
ggplot(aes(x = x, y = y)) +
geom_point() +
geom_text(aes(y = y.label, label = name)) +
# use 2 geom_curve() layers with different curvatures, such that all segments align
# inwards inside the circle
geom_curve(data = stats2 %>% filter(x.start > 0),
aes(x = x.start, y = y.start,
xend = x.end, yend = y.end,
color = to),
curvature = -0.3,
arrow = arrow(angle=15, ends='first',
length=unit(0.03,'npc'),
type='closed')) +
geom_curve(data = stats2 %>% filter(x.start <= 0),
aes(x = x.start, y = y.start,
xend = x.end, yend = y.end,
color = to),
curvature = 0.3,
arrow = arrow(angle=15, ends='first',
length=unit(0.03,'npc'),
type='closed')) +
expand_limits(x = c(-plot.range, plot.range),
y = c(-plot.range, plot.range)) +
coord_equal() +
theme_void()
p
如果你想要极地网格线，也可以使用 geom_spoke() 和 ggfortify 包的 geom_circle():
library(ggforce)
p +
geom_spoke(data = data.frame(x = 0,
y = 0,
angle = pi * seq(from = 0,
to = 2,
length.out = 9), # number of spokes + 1
radius = plot.range),
aes(x = x, y = y, angle = angle, radius = radius),
inherit.aes = FALSE,
color = "grey") +
geom_circle(data = data.frame(x0 = 0,
y0 = 0,
r = seq(from = 0,
to = plot.range,
length.out = 4)), # number of concentric circles + 1
aes(x0 = x0, y0 = y0, r = r),
inherit.aes = FALSE,
color = "grey", fill = NA)
（注意：如果您真的想要这些伪网格线，请在 之前 绘制其他几何图层。）