当值四舍五入为整数时，geom_col 未使用 stat_identify

Question

我正在尝试使用 geom_col 来绘制时间序列（年度和季度）值的列图表。

当我使用 Zoo 包的 YearQtr 数据类型作为 x 轴值并将 y 轴值四舍五入为整数时，geom_col 似乎没有使用默认 postion = 'identity' 用于根据每次出现的 y 值确定柱形栏高度。相反，它似乎切换到 position = 'count' 并将四舍五入的 y 值视为因子，计算每个因子值的出现次数（例如，3 次出现四舍五入y 值 = 11)

如果我切换到 geom_line，图表就可以使用季度 x 轴值和四舍五入的 y 轴值。

library(zoo)
library(ggplot2)

Annual.Periods <- seq(to = 2020, by = 1, length.out = 8) # 8 years
Quarter.Periods <- as.yearqtr(seq(to = 2020, by = 0.25, length.out = 8)) # 8 Quarters

Values <- seq(to = 11, by = 0.25, length.out = 8)

Data.Annual.Real <- data.frame(X = Annual.Periods, Y = round(Values, 1))
Data.Annual.Whole <- data.frame(X = Annual.Periods, Y = round(Values, 0))
Data.Quarter.Real <- data.frame(X = Quarter.Periods, Y = round(Values, 1))
Data.Quarter.Whole <- data.frame(X = Quarter.Periods, Y = round(Values, 0))

ggplot(data = Data.Annual.Real, aes(X, Y)) + geom_col()
ggplot(data = Data.Annual.Whole, aes(X, Y)) + geom_col()
ggplot(data = Data.Quarter.Real, aes(X, Y)) + geom_col()
ggplot(data = Data.Quarter.Whole, aes(X, Y)) + geom_col() # appears to treat y-values as factors and uses position = 'count' to count occurrences (e.g., 3 occurrences have a rounded Value = 11)

ggplot(data = Data.Quarter.Whole, aes(X, Y)) + geom_line() 

rstudioapi::versionInfo()
# $mode
# [1] "desktop"
# 
# $version
# [1] ‘1.3.959’
# 
# $release_name
# [1] "Middlemist Red"

sessionInfo()
# R version 4.0.0 (2020-04-24)
# Platform: x86_64-apple-darwin17.0 (64-bit)
# Running under: macOS Mojave 10.14.6
# 
# Matrix products: default
# BLAS:   /System/Library/Frameworks/Accelerate.framework/Versions/A/Frameworks/vecLib.framework/Versions/A/libBLAS.dylib
# LAPACK: /Library/Frameworks/R.framework/Versions/4.0/Resources/lib/libRlapack.dylib
# 
# locale:
#   [1] en_US.UTF-8/en_US.UTF-8/en_US.UTF-8/C/en_US.UTF-8/en_US.UTF-8
# 
# attached base packages:
#   [1] stats     graphics  grDevices utils     datasets  methods   base     
# 
# other attached packages:
#   [1] ggplot2_3.3.1 zoo_1.8-8

Answer 1

ggplot 尝试猜测其 geom_col() 函数的方向，这意味着哪个变量用作条形的基础，哪个变量作为要表示的值。显然你的 Y- 变量中没有任何小数，它选择它作为它的基础（虽然它保持数字，没有转换为因子），并总结你的季度。

对于这种情况，您可以通过 orientation= 参数向 geom_col() 提供使用什么变量作为柱形基础的信息：

ggplot(data = Data.Quarter.Whole, aes(X, Y)) + geom_col(orientation = "x")

编辑：我刚刚看到 Roman 在评论中回答了它。

当值四舍五入为整数时，geom_col 未使用 stat_identify

geom_col is not using stat_identify when values are rounded to whole numbers

r

ggplot2

zoo

geom-col