R Markdown 中的内联 dplyr

Question

我希望将一些 R 代码内联到我正在写的一篇文章中。以下是可以的：

The quick brown fox jumped over \`r 2+2\` lazy dogs

The quick brown fox jumped over 4 lazy dogs

但是当我尝试将 dplyr 与以下数据框结合使用时：

structure(list(name = structure(c(2L, 1L, 3L), .Label = c("Cat", 
"Dog", "Horse"), class = "factor"), n = c(4L, 3L, 8L)), .Names = c("name", 
"n"), class = "data.frame", row.names = c(NA, -3L))

它坏了：

The quick brown fox jumped over \`r as.numeric(temp %>% filter(name=="dog") %>% select(n)\` lazy dogs

Quitting from lines 80-81 (QuickBrown.Rmd)
Error in base::parse(text = code, keep.source = FALSE) : 
 <text>:2:0: unexpected end of input
1: as.numeric(temp %>% filter(name=="Dog") %>% select(
   ^

尝试使用块对象让我更接近，尤其是结果="asis":

The quick brown fox jumped over 
```{r results="asis", echo=FALSE}
df <- as.numeric(temp %>% filter(name=="Dog") %>% select(n))
print(df[,1][[1]])
```
lazy dogs

The quick brown fox jumped over [1] 4 lazy dogs

但我不知道如何去掉索引号 [1]。我怎样才能最好地将 dplyr 结果与 R Markdown 内联或使用块结合起来，我怎样才能去掉索引号？

Answer 1

我会试试

```{r, echo=FALSE}
library(magrittr) # for %$% extraction
x <- temp %>% filter(name=="Dog") %>% slice(1) %$% n)
```

敏捷的棕色狐狸跳过了 `r x` 懒狗

但是你也可以使用 dplyr inline。我测试成功了：

---
title: "test"
output: html_document
---

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

## R Markdown

here's a `r mtcars %>% slice(1) %$% gear` test with dplyr.

R Markdown 中的内联 dplyr

inline dplyr in R Markdown

r

r-markdown

dplyr