调整 Shiny RMarkdown 报告中的大图大小

Posted 2023-02-16

【中文标题】调整 Shiny RMarkdown 报告中的大图大小

【英文标题】：Adjust for large figure size in Shiny RMarkdown report

【发布时间】：2021-11-04 11:46:06

【问题描述】：

我正在开发一个 Shiny RMarkdown 报告，其中包含一个部分，该部分允许用户通过基于不同变量（例如主题、课程、作业）对数据集进行分组来创建不同的山脊线图。但是，一些变量只有几个组（例如主题），而其他变量有很多组（例如分配）。对于具有许多组的变量，结果图变得不可读，因此我想增加图形大小或允许用户以某种方式向下滚动图形。有人对我如何做到这一点有任何建议吗？ （下面带有虚拟数据的示例 Rmd 文件）

---
title: "Test"
author: "R User"
date: "9/7/2021"
output: html_document
runtime: shiny
---

```r setup, include=FALSE
knitr::opts_chunk$set(echo = TRUE)
library(ggplot2)

# example data
df <- data.frame(
  subject = c(rep("A", 1000), rep("B", 1000), rep("C", 1000)),
  course = rep(paste0("Course ", as.character(1:300)), 10),
  value = rnorm(3000)
)
```

## Modify figure size

I would like to modify the figure size so the ridgelines are still readable when grouped by course, either by making the figure size larger overall or allowing the user to scroll down the figure.

```r, echo=FALSE
inputPanel(
  selectInput("group", label = "Group",
              choices = c("subject", "course"))
)

renderPlot(
  ggplot(df, aes(y = !!as.symbol(input$group), x = value)) +
    ggridges::geom_density_ridges(color = "grey95", fill = "grey50", alpha = 0.5) +
    geom_boxplot(fill = "grey95", color = "grey40", width = 0.2, outlier.shape = NA) +
    labs(y = "") +
    theme_minimal()
)
```

【参考方案1】：

我们可以添加一个滑动条，让用户选择情节的高度，这样当他们觉得太挤时，可以增加高度。

---
title: "Test"
author: "R User"
date: "9/7/2021"
output: html_document
runtime: shiny
---

```r setup, include=FALSE
knitr::opts_chunk$set(echo = TRUE)
library(ggplot2)
library(shiny)
# example data
df <- data.frame(
  subject = c(rep("A", 1000), rep("B", 1000), rep("C", 1000)),
  course = rep(paste0("Course ", as.character(1:300)), 10),
  value = rnorm(3000)
)
```

## Modify figure size

I would like to modify the figure size so the ridgelines are still readable when grouped by course, either by making the figure size larger overall or allowing the user to scroll down the figure.

```r, echo=FALSE
inputPanel(
  selectInput("group", label = "Group",
              choices = c("subject", "course")),
  sliderInput("p_height", "Plot height", value = 600, min = 400, max = 1000, step = 50, round = TRUE)
)

renderPlot(
  ggplot(df, aes(y = !!as.symbol(input$group), x = value)) +
    ggridges::geom_density_ridges(color = "grey95", fill = "grey50", alpha = 0.5) +
    geom_boxplot(fill = "grey95", color = "grey40", width = 0.2, outlier.shape = NA) +
    labs(y = "") +
    theme_minimal()
, height = exprToFunction(input$p_height))
```

将默认的value、minmax更改为您想要的数字，单位为像素。