Dynamic Markdown YAML

Kevin Feasel



Steph Locke shows how to use the params section of a YAML header to enable parameter reuse:

You may already know the trick about making the date dynamic to whatever date the report gets rendered on by using the inline R execution mode of rmarkdown to insert a value.

title: "My report"
date: "`r Sys.Date()`"
output: pdf_document

What you may not already know is that YAML fields get evaluated sequentially so you can use a value created further up in the params section, to use it later in the block.

Click through to see how it’s done.

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