beamer rmarkdown 演示文稿无法编织 pdf 文件，而是编织也未编织的 html 文档

Question

I have a beamer rmarkdown file for preparing PDF presentation as teaching material. However, when I click knit with pdf, the output is displayed in html document, instead of beamer_presentation (pdf). my yaml is:

Thanking all in advance.

Earlier it was knitting properly but after some time it started giving this problem I have checked all 'helps' at various forums, but the problem persists. I have even installed tinyverse and installed/removed MikTex and restarted the system to solve the problem.

---
title: "Mathematics for Finance"  
author:   
  - Dr. XXXX  
institute:   
  - YYYY  
date: "June-July 2019"
output:   
  beamer_presentation:  
    incremental: false  
    theme: "AnnArbor"  
    colortheme: "wolverine"  
    fonttheme: "structuresmallcapsserif"  
    toc: true   
    slide_level: 2  
    fig_width: 5  
    fig_height: 4  
    fig_caption: true  
    highlight: tango
    link-citations: yes  
    urlcolor: red  
    linkcolor: red  
    citecolor: blue  
---

No error message is displayed, simply HTM document is executed that too blank!

"C:/Users/Kulbirs/ANACON~1/envs/rstudio/Scripts/pandoc" +RTS -K512m -RTS beamertest1.utf8.md --to html4 --from markdown+autolink_bare_uris+ascii_identifiers+tex_math_single_backslash+smart --output beamertest1.html --email-obfuscation none --self-contained --standalone --section-divs --template "C:\\Users\\Kulbirs\\Documents\\R\\win-library\\3.6\\rmarkdown\\rmd\\h\\default.html" --no-highlight --variable highlightjs=1 --variable "theme:bootstrap" --include-in-header "C:\\Users\\Kulbirs\\AppData\\Local\\Temp\\RtmpgnjFVR\\rmarkdown-str56854a3563d.html" --mathjax --variable "mathjax-url: https://mathjax.rstudio.com/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML " --metadata pagetitle=beamertest1.utf8.md

Output created: beamertest1.html

Answer 1

The problem are the lines

link-citations: yes  
urlcolor: red  
linkcolor: red  
citecolor: blue  

If you really, really, really want to have coloured links, you could add

header-includes:
  - \hypersetup{colorlinks, urlcolor=red, linkcolor=red, citecolor=blue}

to your header, but this is really, really, really a bad idea with beamer, because this breaks all carefully chosen design decisions made by your theme.