add mathjax YAML parameter to support mathjax expressions; closes daa…

…ttali#195

CHANGELOG.md

@@ -1,6 +1,7 @@
 ## Unreleased version
 - BREAKING CHANGE: Allow changing the order of the social network links that appear in the footer (#1152)
 - BREAKING CHANGE: `google-scholar` social network link no longer requires the prefix `citations?user=`; if you previously set this parameter, it needs to be updated (#1189)
+- Added `mathjax` YAML parameter to allow support for MathJax, used to write LaTeX expressions (#195)
 - Added explicit support for favicons, you only need to add a `favicon.ico` file to the root directory
 - The footer of a page always sticks to the bottom, even on short pages (#576)
 - Added `author` YAML parameter to allow specifying the author(s) of a post (#1220)

README.md

@@ -132,7 +132,7 @@ You can look at the top of [`aboutme.md`](https://raw.githubusercontent.com/daat
 
 # Supported parameters
 
-Below is a list of the parameters that Beautiful Jekyll supports (any of these can be added to the YAML front matter of any page). Remember to also look in the `_config.yml` file to see additional site-wide settings.
+Below is a list of the parameters that Beautiful Jekyll supports (any of these can be added to the YAML front matter of any page). Remember to also look in the `_config.yml` file to see additional site-wide settings. If there's a parameter that you want to apply to the entire site instead of one specific page, check out [this FAQ answer](https://beautifuljekyll.com/faq/#default-params).
 
 ## Main parameters
 
@@ -146,6 +146,7 @@ tags        | List of tags to categorize the post. Separate the tags with commas
 cover-img   | Include a large full-width image at the top of the page. You can either provide the path to a single image (eg. `"/path/to/img"`) , or a list of images to cycle through (eg. `["/path/img1", "/path/img2"]`). If you want to add a caption to an image, then you must use the list notation (use `[]` even if you have only one image), and each image should be provided as `"/path/to/img" : "Caption of image"`.
 thumbnail-img | For blog posts, if you want to add a thumbnail that will show up in the feed, use `thumbnail-img: /path/to/image`. If no thumbnail is provided, then `cover-img` will be used as the thumbnail. You can use `thumbnail-img: ""` to disable a thumbnail.
 comments    | If you want do add comments to a specific page, use `comments: true`. Comments only work if you enable one of the comments providers (Facebook, disqus, staticman, utterances, giscus, CommentBox) in `_config.yml` file. Comments are automatically enabled on blog posts but not on other pages; to turn comments off for a specific post, use `comments: false`.
+mathjax     | If you want to use LaTeX formulas, you need to enable MathJax. Note that in MathJax you need to use `$$` and `\\(` to start and end expressions
 
 ## Parameters for SEO and social media sharing
 
@@ -210,7 +211,7 @@ Congratulations on making it this far! You now have all the tools to easily buil
 
 - After you get comfortable with the basics of writing in markdown, I suggest taking a look at this [sample post](https://beautifuljekyll.com/2020-02-28-sample-markdown/) and [the code that created it](https://raw.githubusercontent.com/daattali/beautiful-jekyll/master/_posts/2020-02-28-sample-markdown.md) to learn some more advanced tips about markdown.
 
-- I highly recommend going over the [*Frequently Asked Questions*](https://beautifuljekyll.com/faq/) to find out answers to questions you may not even know you have. Every few months I suggest checking the [*What's New?*](https://beautifuljekyll.com/updates/) page to see if there are new features, and learn [how to update your site to the newest version](https://beautifuljekyll.com/faq/#updating) when it's time.
+- I **highly recommend** going over the [*Frequently Asked Questions*](https://beautifuljekyll.com/faq/) to find out answers to questions you may not even know you have. Every few months I suggest checking the [*What's New?*](https://beautifuljekyll.com/updates/) page to see if there are new features, and learn [how to update your site to the newest version](https://beautifuljekyll.com/faq/#updating) when it's time.
 
 - You can also check out the [advanced installation methods](https://beautifuljekyll.com/getstarted/#install-steps-hard) that give you a little more control but are harder to use. Keep in mind that Beautiful Jekyll was primarily designed to be used as a GitHub theme, so you will not get any support if you choose one of the Ruby installation methods. 
 

_includes/head.html

@@ -62,6 +62,7 @@
   {% include gtm_head.html %}
   {% include google_analytics.html %}
   {% include cloudflare_analytics.html %}
+  {% include mathjax.html %}
 
   {% if layout.common-ext-css %}
     {% for css in layout.common-ext-css %}

_includes/mathjax.html

@@ -0,0 +1,12 @@
+{% if page.mathjax %}
+<script type="text/javascript">
+  MathJax = {
+    options: {
+      skipHtmlTags: [
+        'script', 'noscript', 'style', 'textarea', 'pre', 'code'
+      ]
+    }
+  };
+</script>
+<script type="text/javascript" async src="https://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML"></script>
+{% endif %}

_posts/2020-02-28-sample-markdown.md

@@ -6,6 +6,7 @@ gh-repo: daattali/beautiful-jekyll
 gh-badge: [star, fork, follow]
 tags: [test]
 comments: true
+mathjax: true
 author: Bill Smith
 ---
 
@@ -27,6 +28,9 @@ Here's a table:
 | Seven | Eight | Six |
 | Two | Three | One |
 
+You can use [MathJax](https://www.mathjax.org/) to write LaTeX expressions. For example:
+When \\(a \ne 0\\), there are two solutions to \\(ax^2 + bx + c = 0\\) and they are $$x = {-b \pm \sqrt{b^2-4ac} \over 2a}.$$
+
 How about a yummy crepe?
 
 ![Crepe](https://beautifuljekyll.com/assets/img/crepe.jpg)