Question

An answer by Nicholas Hamilton指定如何使用R表达式在Markdown的PDF和HTML输出中使用彩色文本。

如果我创建一个RMarkdown文档，我不会感到高兴，警告消息是

colFmt（“ MY RED TEXT”，“ red”）中的错误：找不到对象'opts_knit' 调用：... inline_exec-> hook_eval-> withVisible-> eval-> eval-> colFmt 执行停止

我想念什么？

复制并粘贴以下RMarkdown：

---
title: "test colour"
author: "mbn"
output: html_document
---

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

## R Markdown

This is an R Markdown document. 

```{r cars}
colFmt = function(x,color){
  outputFormat = opts_knit$get("rmarkdown.pandoc.to")
  if(outputFormat == 'latex')
    paste("\\textcolor{",color,"}{",x,"}",sep="")
  else if(outputFormat == 'html')
    paste("<font color='",color,"'>",x,"</font>",sep="")
  else
    x
}
```

## Test colour now

`r colFmt("MY RED TEXT",'red')`

Answer 1

将opts_knit$get更改为knitr::opts_knit$get，您的代码应该可以使用。

请参见https://stat.ethz.ch/R-manual/R-devel/library/base/html/ns-dblcolon.html

Answer 2

这是一个rmarkdown代码的示例，该代码自包含且有效，并使用十六进制颜色ID在pdf和html中提供一致的颜色。感谢Kenji的贡献指出我需要knitr库。

---
title: "test colour"
author: "mbn"
output: html_document
#output: pdf_document
header-includes:
  \usepackage[usenames,dvipsnames]{xcolor}
---

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

```

## R Markdown

This is an R Markdown document. 

```{r cars}
colFmt = function(x,color){
  outputFormat = opts_knit$get("rmarkdown.pandoc.to")
  if(outputFormat == 'latex')
    paste("\\textcolor[HTML]{",color,"}{",x,"}",sep="")
  else if(outputFormat == 'html')
    paste("<font color='",color,"'>",x,"</font>",sep="")
  else
    x
}
```

## Test colour now

`r colFmt("My colored text favorite green latex/pdf and html",'7ac143')`

在HTML和PDF输出中指定颜色

2 个答案: