我需要应用cut一个连续变量以在 ggplot2 中使用 Brewer 色标显示它，如在 ggplot2 中使用 scale_fill_brewer() 函数为数据设置断点。连续变量是一个相对差异，我想将数据格式化为“18.2 %”而不是“0.182”。有没有简单的方法来实现这一目标？
x <- runif(100)
levels(cut(x, breaks=10))
[1] "(0.0223,0.12]" "(0.12,0.218]" "(0.218,0.315]" "(0.315,0.413]"
[5] "(0.413,0.511]" "(0.511,0.608]" "(0.608,0.706]" "(0.706,0.804]"
[9] "(0.804,0.901]" "(0.901,0.999]"
例如，我希望第一级显示为(2.23 %, 12 %]. 有更好的选择cut吗？
我已经cut_format()在我的包的 0.2-3 版中实现了kimisc，0.3 版现在在 CRAN 上。
# devtools::install_github("krlmlr/kimisc")
x <- seq(0.1, 0.9, by = 0.2)
breaks <- seq(0, 1, by = 0.25)
cut(x, breaks)
## [1] (0,0.25] (0.25,0.5] (0.25,0.5] (0.5,0.75] (0.75,1]
## Levels: (0,0.25] (0.25,0.5] (0.5,0.75] (0.75,1]
cut_format(x, breaks, format_fun = scales::percent)
## [1] (0%, 25%] (25%, 50%] (25%, 50%] (50%, 75%] (75%, 100%]
## Levels: (0%, 25%] (25%, 50%] (50%, 75%] (75%, 100%]
它仍然不完美，传递中断次数（如在原始示例中）还不起作用。
gsub将原始数据乘以 100 后使用一些正则表达式：
gsub("([0-9.]+)","\\1%",levels(cut(x*100,breaks=10)))
[1] "(0.449%,10.4%]" "(10.4%,20.3%]" "(20.3%,30.2%]" "(30.2%,40.2%]" "(40.2%,50.1%]" "(50.1%,60%]" "(60%,69.9%]" "(69.9%,79.9%]" "(79.9%,89.8%]" "(89.8%,99.7%]"
为什么不复制代码cut.default并创建您自己的具有修改级别的版本？请参阅此要点。
更改了两行：
第 22 行：ch.br <- formatC(breaks, digits = dig, width = 1)更改为ch.br <- formatC(breaks*100, digits = dig, width = 1).
第 29 行：else "[", ch.br[-nb], ",", ch.br[-1L], if (right)更改为else "[", ch.br[-nb], "%, ", ch.br[-1L], "%", if (right)
其余的都是一样的。它在行动中：
library(devtools)
source_gist(4593967)
set.seed(1)
x <- runif(100)
levels(cut2(x, breaks=10))
# [1] "(1.24%, 11%]" "(11%, 20.9%]" "(20.9%, 30.7%]" "(30.7%, 40.5%]" "(40.5%, 50.3%]"
# [6] "(50.3%, 60.1%]" "(60.1%, 69.9%]" "(69.9%, 79.7%]" "(79.7%, 89.5%]" "(89.5%, 99.3%]"
一个老问题的新答案。
您可以使用label参数传递一个函数来格式化标签。我将使用gsubfn和scales::percent
library(gsubfn)
library(scales)
pcut <- function(x) gsubfn('\\d\\.\\d+', function(x) percent(as.numeric(x)),xx)
d <- data.frame(x=runif(100))
ggplot(d,aes(x=x,y=seq_along(x))) +
geom_point(aes(colour = cut(x, breaks = 10))) +
scale_colour_brewer(name = 'x', palette = 'Spectral', label = pcut)
我的包cutr与@krlmlr 的功能非常相似（直到现在我才知道）。
cutf只是cut带有一个format_fun参数，...它被传递给，而format_fun不是cut.cut_format
smart_cut具有更多功能和不同的默认值：
devtools::install_github("moodymudskipper/cutr")
library(cutr)
x <- seq(0.1, 0.9, by = 0.2)
breaks <- seq(0, 1, by = 0.25)
cutf(x, breaks, format_fun = scales::percent)
# [1] (0%,25%] (25%,50%] (25%,50%] (50%,75%] (75%,100%]
# Levels: (0%,25%] (25%,50%] (50%,75%] (75%,100%]
smart_cut(x, breaks, format_fun = scales::percent,simplify = F, closed = "right")
# [1] [0%,25%] (25%,50%] (25%,50%] (50%,75%] (75%,100%]
# Levels: [0%,25%] < (25%,50%] < (50%,75%] < (75%,100%]
Hmisc::cut2现在也有一个formatfun论点：
library(Hmisc)
Hmisc::cut2(x, breaks, formatfun = scales::percent)
# [1] [0%,25%) [25%,50%) [50%,75%) [50%,75%) [75%,100%]
# Levels: [0%,25%) [25%,50%) [50%,75%) [75%,100%]
新的{santoku} 包现在提供了一种在开发版本中执行此操作的方法：
library(santoku)
set.seed(20200607)
x <- runif(20)
chop_evenly(x, 10, labels = lbl_intervals(fmt = percent))
#> [1] [33.13%, 42.11%) [60.08%, 69.06%) [69.06%, 78.04%) [69.06%, 78.04%)
#> [5] [87.02%, 96%] [6.193%, 15.17%) [15.17%, 24.15%) [6.193%, 15.17%)
#> [9] [33.13%, 42.11%) [6.193%, 15.17%) [87.02%, 96%] [51.1%, 60.08%)
#> [13] [42.11%, 51.1%) [6.193%, 15.17%) [42.11%, 51.1%) [6.193%, 15.17%)
#> [17] [6.193%, 15.17%) [69.06%, 78.04%) [78.04%, 87.02%) [87.02%, 96%]
#> 9 Levels: [6.193%, 15.17%) [15.17%, 24.15%) ... [87.02%, 96%]
tab_evenly(x, 10, labels = lbl_intervals(fmt = scales::label_percent(accuracy = 0.1)))
#> x
#> [6.2%, 15.2%) [15.2%, 24.2%) [33.1%, 42.1%) [42.1%, 51.1%) [51.1%, 60.1%)
#> 6 1 2 2 1
#> [60.1%, 69.1%) [69.1%, 78.0%) [78.0%, 87.0%) [87.0%, 96.0%]
#> 1 3 1 3
由reprex 包（v0.3.0）于 2020 年 6 月 9 日创建