facet_grid 中的免费色阶
Free colour scales in facet_grid
假设我有以下数据框:
# Set seed for RNG
set.seed(33550336)
# Create toy data frame
loc_x <- c(a = 1, b = 2, c = 3)
loc_y <- c(a = 3, b = 2, c = 1)
scaling <- c(temp = 100, sal = 10, chl = 1)
df <- expand.grid(loc_name = letters[1:3],
variables = c("temp", "sal", "chl"),
season = c("spring", "autumn")) %>%
mutate(loc_x = loc_x[loc_name],
loc_y = loc_y[loc_name],
value = runif(nrow(.)),
value = value * scaling[variables])
看起来像,
# > head(df)
# loc_name variables season loc_x loc_y value
# 1 a temp spring 1 3 86.364697
# 2 b temp spring 2 2 35.222573
# 3 c temp spring 3 1 52.574082
# 4 a sal spring 1 3 0.667227
# 5 b sal spring 2 2 3.751383
# 6 c sal spring 3 1 9.197086
我想使用 variables
和 season
将这些数据绘制在小平面网格中以定义面板,如下所示:
g <- ggplot(df) + geom_point(aes(x = loc_name, y = value), size = 5)
g <- g + facet_grid(variables ~ season)
g
如您所见,不同的 variables
具有非常不同的尺度。因此,我使用 scales = "free"
来说明这一点。
g <- ggplot(df) + geom_point(aes(x = loc_name, y = value), size = 5)
g <- g + facet_grid(variables ~ season, scales = "free")
g
很方便。现在,假设我想这样做,但是用 loc_x
和 loc_y
绘制点,并用颜色而不是 y 位置表示 value
:
g <- ggplot(df) + geom_point(aes(x = loc_x, y = loc_y, colour = value),
size = 5)
g <- g + facet_grid(variables ~ season, scales = "free")
g <- g + scale_colour_gradient2(low = "#3366CC",
mid = "white",
high = "#FF3300",
midpoint = 50)
g
请注意,颜色 比例不是免费的,并且与第一个数字一样,sal
和 chl
的值不容易读取。
我的问题:除了颜色之外,是否可以做与 scales = "free"
等效的事情,以便每一行(在本例中)都有一个单独的颜色条?或者,我是否必须绘制每个变量(即图中的行)并使用 cowplot
?
之类的东西将它们拼凑在一起
使用dplyr
的开发版:
library(dplyr)
library(purrr)
library(ggplot2)
library(cowplot)
df %>%
group_split(variables, season) %>%
map(
~ggplot(., aes(loc_x, loc_y, color = value)) +
geom_point(size = 5) +
scale_colour_gradient2(
low = "#3366CC",
mid = "white",
high = "#FF3300",
midpoint = median(.$value)
) +
facet_grid(~ variables + season, labeller = function(x) label_value(x, multi_line = FALSE))
) %>%
plot_grid(plotlist = ., align = 'hv', ncol = 2)
假设我有以下数据框:
# Set seed for RNG
set.seed(33550336)
# Create toy data frame
loc_x <- c(a = 1, b = 2, c = 3)
loc_y <- c(a = 3, b = 2, c = 1)
scaling <- c(temp = 100, sal = 10, chl = 1)
df <- expand.grid(loc_name = letters[1:3],
variables = c("temp", "sal", "chl"),
season = c("spring", "autumn")) %>%
mutate(loc_x = loc_x[loc_name],
loc_y = loc_y[loc_name],
value = runif(nrow(.)),
value = value * scaling[variables])
看起来像,
# > head(df)
# loc_name variables season loc_x loc_y value
# 1 a temp spring 1 3 86.364697
# 2 b temp spring 2 2 35.222573
# 3 c temp spring 3 1 52.574082
# 4 a sal spring 1 3 0.667227
# 5 b sal spring 2 2 3.751383
# 6 c sal spring 3 1 9.197086
我想使用 variables
和 season
将这些数据绘制在小平面网格中以定义面板,如下所示:
g <- ggplot(df) + geom_point(aes(x = loc_name, y = value), size = 5)
g <- g + facet_grid(variables ~ season)
g
如您所见,不同的 variables
具有非常不同的尺度。因此,我使用 scales = "free"
来说明这一点。
g <- ggplot(df) + geom_point(aes(x = loc_name, y = value), size = 5)
g <- g + facet_grid(variables ~ season, scales = "free")
g
很方便。现在,假设我想这样做,但是用 loc_x
和 loc_y
绘制点,并用颜色而不是 y 位置表示 value
:
g <- ggplot(df) + geom_point(aes(x = loc_x, y = loc_y, colour = value),
size = 5)
g <- g + facet_grid(variables ~ season, scales = "free")
g <- g + scale_colour_gradient2(low = "#3366CC",
mid = "white",
high = "#FF3300",
midpoint = 50)
g
请注意,颜色 比例不是免费的,并且与第一个数字一样,sal
和 chl
的值不容易读取。
我的问题:除了颜色之外,是否可以做与 scales = "free"
等效的事情,以便每一行(在本例中)都有一个单独的颜色条?或者,我是否必须绘制每个变量(即图中的行)并使用 cowplot
?
使用dplyr
的开发版:
library(dplyr)
library(purrr)
library(ggplot2)
library(cowplot)
df %>%
group_split(variables, season) %>%
map(
~ggplot(., aes(loc_x, loc_y, color = value)) +
geom_point(size = 5) +
scale_colour_gradient2(
low = "#3366CC",
mid = "white",
high = "#FF3300",
midpoint = median(.$value)
) +
facet_grid(~ variables + season, labeller = function(x) label_value(x, multi_line = FALSE))
) %>%
plot_grid(plotlist = ., align = 'hv', ncol = 2)