! LaTeX Error: Option clash for package fontspec

Question

I am trying to generate pdf from rmarkdown file using xelatex as latex engine. The file generates pdf while using pdflatex as latex engine. But, if I use xelatex, the file is giving the following error.

`! LaTeX Error: Option clash for package fontspec.

Error: LaTeX failed to compile cvGeneration.tex. See https://yihui.org/tinytex/r/#debugging for debugging tips. See cvGeneration.log for more info. Execution halted`

When I checked the log file I got the following few lines only.

*`! LaTeX Error: Option clash for package fontspec. See the LaTeX manual or LaTeX Companion for explanation. Type H for immediate help. ...

l.65 ...Package[\eu@zf@math]{fontspec}[2008/08/09]

The package fontspec has already been loaded with options: [] There has now been an attempt to load it with options [no-math] Adding the global options: ,no-math to your \documentclass declaration may fix this. Try typing to proceed.`*

Can anyone tell me why this problem is generating particularly for xelatex? I am trying to implement xelatex, since it supports UTF-8 character. Thanks In advance.

My YAML header is given below:

  params:
  cvName: RJ MIMI
  name: "`r params$cvName`"
  address: 
  www: 
  phone:
  email: 
  linkedin: 
  headcolor: "00008B"
  date: "`r format(Sys.time(), '%B')`"
  output:
    vitae::hyndman:
      keep_tex: true
      latex_engine: xelatex
  header_includes:
    - \ExecuteBibliographyOptions{useprefix=true}
    - renewcommand{\bibfont}{\normalfont\fontsize{10}{12.4}\sffamily}

Answer 1

This is pretty far down the road, however, the easiest way to get past the fontspec error is to set defaultfontfeatures. (fontspec is the default in RMarkdown.)

I don't have all that is going into your code here, update your header_includes to:

header_includes:
    - \ExecuteBibliographyOptions{useprefix=true}
    - \defaultfontfeatures(Ligatures = TeX)
    - renewcommand{\bibfont}{\normalfont\fontsize{10}{12.4}\sffamily}

This may still give you warnings because it's not right, but it works.