Sometimes it is necessary to modify the default formatting of your R Markdown output. For example, you might want to position content at the top of a beamer slide by default. First of all then, you need the default template to modify it. Here is a list of the templates that R Markdown uses for its conversion: https://github.com/jgm/pandoc-templates. Note that these are pandoc templates because pandoc effectively creates your output file.
Save your ouput format’s template into the folder in which your .Rmd file is located and add this to your YAML header (this is an example for pdf output):
---
output:
pdf_document:
template: default.latex
---Note that whitespace matters in YAML headers: the indentation is necessary and implicates that ‘template’ is an extra argument to ‘pdf_document’. This, for example, would cause the conversion to fail:
---
output:
pdf_document:
template: default.latex
---