是否可以直接使用knitr函数knit2pdf()与R Markdown(Rmd)文件？我已经看过各种教程/课堂笔记似乎表明它可以在这里和这里(Ctrl + F"knit2pdf"中的任何一个).
但是当我拿一个简单的rmd文件(保存为"test.rmd")时
---
title: "knit2pdf test"
author: "A Aaronson"
date: "Thursday, February 19, 2015"
output: pdf_document
---
This is an R Markdown document. Markdown is a simple formatting syntax for authoring HTML, PDF, and MS Word documents. For more details on using R Markdown see <http://rmarkdown.rstudio.com>.
When you click the **Knit** button a document will be generated that includes both content as well as the output of any embedded R code chunks within …我一直在dplyr tbl_df中循环遍历值,尝试打印两列的唯一组合.经过多次试验和错误后,我只能通过将tbl_df转换回标准data.frame来获得所需的输出.我知道两种结构之间的主要区别,但我仍然无法理解我看到的每种结构的不同输出.
例如,使用此数据
hospital <- rep(c("Hospital 1", "Hospital 2", "Hospital 3"), 3)
ward <- LETTERS[1:2]
hospitals <- data.frame(cbind(hospital, ward))
hospitals[order(hospitals$hospital, hospitals$ward), ]
# hospital ward
# 1 Hospital 1 A
# 7 Hospital 1 A
# 4 Hospital 1 B
# 5 Hospital 2 A
# 2 Hospital 2 B
# 8 Hospital 2 B
# 3 Hospital 3 A
# 9 Hospital 3 A
# 6 Hospital 3 B
和以下循环
for(hosp in unique(hospitals$hospital)){
for(wa in unique(hospitals[hospitals$hospital==hosp, "ward"])){
print(paste(hosp, wa, …