[英]customize legend in ggplot2 with sf objects
I am plotting (mapping) sf
objects with ggplot2
.我正在使用
ggplot2
绘制(映射) sf
对象。 My understanding is that since version 2.2.1 ggplot2
contains the geom geom_sf
, for simple feature objects.我的理解是,由于版本 2.2.1
ggplot2
包含 geom geom_sf
,用于简单的特征对象。
I can produce the exact map that I want by doing the following:我可以通过执行以下操作来生成我想要的确切地图:
library(sf)
library(ggplot2)
# some points to start with
a <- st_as_sf(data.frame(lon = c(1,4,6), lat = c(0,0,-3)), coords = c('lon', 'lat'))
b <- st_as_sf(data.frame(lon = c(2.5,4), lat = c(-4.5,-5)), coords = c('lon', 'lat'))
# circles around those points
buf.a <- st_buffer(a, 1)
buf.b <- st_buffer(b, 1)
# colors to mark the points
sol.a = rgb(1,0,0)
sol.b = rgb(0,0,1)
# colors to fill the circles
fil.a = adjustcolor(sol.a, alpha.f = .25)
fil.b = adjustcolor(sol.b, alpha.f = .25)
# the plot I want
g = ggplot() +
geom_sf(data = buf.a, fill = fil.a, color = NA) +
geom_sf(data = buf.b, fill = fil.b, color = NA) +
geom_sf(data = a, color = sol.a, shape = 20, size = 3) +
geom_sf(data = b, color = sol.b, shape = 20, size = 3)
g
which produces产生
This is what I want except that it is missing a legend.这就是我想要的,只是它缺少一个传说。 For that, I am doing
为此,我正在做
cols.fill = c("GROUP A" = fil.a, "GROUP B" = fil.b)
cols.sol = c("GROUP A" = sol.a, "GROUP B" = sol.b)
g = ggplot() +
geom_sf(data = buf.a, color = NA, aes(fill = 'GROUP A')) +
geom_sf(data = buf.b, color = NA, aes(fill = 'GROUP B')) +
geom_sf(data = a, shape = 20, size = 3, aes(color = 'GROUP A')) +
geom_sf(data = b, shape = 20, size = 3, aes(color = 'GROUP B')) +
scale_fill_manual(name = "circles", values = cols.fill) +
scale_color_manual(name = "points", values = cols.sol)
g
which gives这使
That's not what I want, because in the legend:那不是我想要的,因为在传说中:
Would be nice if the legend could respect the transparency of my colors (which it did in this example).如果图例可以尊重我的颜色的透明度(在本例中就是这样做的),那就太好了。
I tried to change the last couple of lines of the above to something like我试图将上面的最后几行更改为类似
scale_fill_manual(name = "circles", values = cols.fill,
guide = guide_legend(override.aes = list(shape = c(19, 19)))) +
scale_color_manual(name = "points", values = cols.sol,
guide = guide_legend(override.aes = list(shape = c(20, 20))))
but that didn't do anything to my plot.但这对我的情节没有任何影响。
Ideas?想法?
Note: If it ends up being simpler for the plot, I could change the structure of the data, eg, by combining objects a
and b
in the same simple feature object and add a column indicating the group (same for buf.a
and buf.b
).注意:如果绘图最终变得更简单,我可以更改数据的结构,例如,通过将对象
a
和b
组合在同一个简单的特征对象中,并添加一列指示组( buf.a
和buf.b
相同) buf.b
)。
Here's how far I managed to get to.这是我设法达到的程度。
g = ggplot() +
geom_sf(data = buf.a, color = NA, aes(fill = 'GROUP A'), show.legend = "point") +
geom_sf(data = buf.b, color = NA, aes(fill = 'GROUP B'), show.legend = "point") +
geom_sf(data = a, shape = 20, size = 3, aes(color = 'GROUP A'), show.legend = "point") +
geom_sf(data = b, shape = 20, size = 3, aes(color = 'GROUP B'), show.legend = "point") +
scale_color_manual(name = "points", values = cols.sol,
guide = guide_legend(override.aes = list(shape = c(20, 20)))) +
scale_fill_manual(name = "circles", values = cols.fill,
guide = guide_legend(override.aes = list(shape = c(20, 20), color = cols.fill, size = 8)))
g
To get rid of the gray background in the legend symbols,要摆脱图例符号中的灰色背景,
g + theme(legend.key = element_rect(fill = "white"))
The only issue here is that the circles do not have the transparency I wanted.这里唯一的问题是圆圈没有我想要的透明度。 This is odd.
这很奇怪。
要获得图例中的透明度需要将其添加到 override.aes 中,请尝试:
guide = guide_legend(override.aes = list(alpha = 0.5, shape = c(20, 20), color = cols.fill, size = 8, )))
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.