Understanding the Behavior of `summary_table` in R Markdown and Knitted HTML

In this article, we will delve into the world of R packages, specifically the qwraps2 package, which provides a convenient way to create tables summarizing various statistics from data. We’ll explore how the summary_table function behaves when used within an R Markdown document versus when knitted as HTML.

Introduction

The qwraps2 package is designed to provide a simple and efficient way to summarize various statistics, such as means, medians, and minimum/maximum values, for different variables in your dataset. One of the key features of this package is its ability to create nicely formatted tables summarizing these statistics.

However, when it comes to rendering these tables within an R Markdown document versus knitting them as HTML, we find that the summary_table function behaves differently in each case. In this article, we will investigate the reasons behind this behavior and provide guidance on how to achieve consistent results across both platforms.

Background

To understand why summary_table behaves differently when used within an R Markdown document versus when knitted as HTML, it’s essential to first explore the underlying mechanics of these two processes.

When working with R Markdown documents, the output is generated by rendering the contents of the .Rmd file into a format suitable for presentation. This involves processing the .Rmd file and generating markdown code, which is then used to create the final HTML document.

On the other hand, when knitting an R Markdown document as HTML, the process involves taking the rendered markdown code from the .Rmd file and converting it into a format suitable for HTML rendering. This step requires using additional tools and configurations to ensure that the resulting HTML is properly formatted.

The `summary_table` Function

The summary_table function from the qwraps2 package provides a convenient way to create tables summarizing various statistics from your data. The basic syntax of this function can be summarized as follows:

summary_table(data, summary = list(...))

Where data is the dataset you wish to summarize and summary is a list of functions specifying which statistics to include in the table.

In our example code snippet, we create a list called our_summary that contains various statistics for different variables:

our_summary &lt;-
  list("Alcohol drunk at the weekend" = 
         list("variable" =~ c("interval"),
              "min" = ~ min(ESS$alcwknd),
              "median" = ~ median(ESS$alcwknd),
              "max" = ~ max(ESS$alcwknd),
              "mean (sd)" = ~ qwraps2::mean_sd(ESS$cgtsday)),
       ...
)

We then pass this our_summary list to the summary_table function, which creates a nicely formatted table summarizing these statistics:

tab &lt;- summary_table(ESS, our_summary)
print(tab, rtitle = "Summary Statistics")

Behavior Within R Markdown Documents

When using the summary_table function within an R Markdown document, the resulting output is rendered as markdown code. This means that the table will appear in the .Rmd file as a formatted string, but it will not be rendered as HTML.

In order to render this table as HTML, we need to use the results = "asis" parameter when calling the summary_table function:

tab &lt;- summary_table(ESS, our_summary)
print(tab, rtitle = "Summary Statistics", results = "asis")

This tells R to generate raw markdown code instead of rendering it as HTML.

Behavior When Knitted as HTML

When knitting an R Markdown document as HTML, the resulting output will depend on how you configure your document. By default, R will render the .Rmd file using the knitr package and create a suitable HTML structure.

However, when using the summary_table function within this process, the resulting table may not be properly formatted unless we take additional steps to ensure that it is rendered correctly as HTML.

Conclusion

In conclusion, our exploration of the behavior of the summary_table function reveals an important distinction between rendering markdown code versus knitted HTML. By understanding how these processes work and using the correct configuration options, you can achieve consistent results across both platforms.

Whether working within an R Markdown document or knitting it as HTML, taking control over the rendering process is key to ensuring that your tables are rendered correctly.

Last modified on 2024-09-15

Understanding the Behavior of summary_table in R Markdown and Knitted HTML