title: R Markdown HTML Number Figures
body: <p>Does anyone know how to number the figures in the captions, for HTML format R Markdown script?</p>
  
  <p>For PDF documents, the caption will say something like:</p>
  
  <blockquote>
    <p>Figure X: Some Caption Text</p>
  </blockquote>
  
  <p>However, the equivalent caption for the HTML version will simply say:</p>
  
  <blockquote>
    <p>Some Caption Text</p>
  </blockquote>
  
  <p>This makes cross-referencing figures by number completely useless.</p>
  
  <p>Here is a minimal example:</p>
  
  <pre><code>---
  title: "My Title"
  author: "Me"
  output:
    pdf_document: default
    html_document: default
  ---
  
  ```{r cars, fig.cap = "An amazing plot"}
  plot(cars)
  ```
  
  
  ```{r cars2, fig.cap = "Another amazing plot"}
  plot(cars)
  ```
  </code></pre>
  
  <p>I have tried setting <code>toc</code>, <code>fig_caption</code> and <code>number_sections</code> within each of the output formats, but this does not seem to change the result.</p>