如何让这个 ggplot2 geom_bar 图中的条形图使用 Rcolorbrewer 调色板？

Posted 2023-02-16

【中文标题】如何让这个 ggplot2 geom_bar 图中的条形图使用 Rcolorbrewer 调色板？

【英文标题】：How do I get the bars in this ggplot2 geom_bar graph to use Rcolorbrewer palette?

【发布时间】：2021-09-12 01:06:20

【问题描述】：

我一直试图让我的图表条显示为 Rcolorbrewer“Set1”调色板，但我尝试的所有操作都会创建一个带有灰色条的图表。这是我尝试过的代码：

total_enrollment_by_year_plot <- ggplot(data = total_enrollment_by_year) +
geom_bar(mapping = aes(x = Year, y = Total_Enrollments), stat = "identity") +
labs(
title = "Total Patient Enrollment by Year, 2018-2020",
x = "Year", # x-axis label
y = "Patients Enrolled") + # y-axis label
scale_color_brewer(palette = "Set1")

我也绝望了，试图创建自己的图例来为每个条形添加颜色，但它也不起作用：

total_enrollment_by_year_plot <- ggplot(data = total_enrollment_by_year) +
geom_bar(mapping = aes(x = Year, y = Total_Enrollments), stat = "identity") +
labs(
title = "Total Patient Enrollment by Year, 2018-2020",
x = "Year", # x-axis label
y = "Patients Enrolled") + # y-axis label
scale_fill_manual("Legend", values = c("2018" = "Green", "2019" = "Blue", "2020"
                                       = "Orange", "All Years" = "Red"))

我做错了什么？

【参考方案1】：

您需要在 aes 中添加填充，并且应该使用 scale_fill_brewer 而不是 scale_color_brewer。

total_enrollment_by_year_plot <- ggplot(data = total_enrollment_by_year) +
geom_bar(mapping = aes(x = Year, y = Total_Enrollments, fill = Year), stat = "identity") +
labs(
title = "Total Patient Enrollment by Year, 2018-2020",
x = "Year", # x-axis label
y = "Patients Enrolled") + # y-axis label
scale_fill_brewer(palette = "Set1")